List of Seminars

 
 

Speaker:

Dr. Aparna Deshpande

Affiliation:

IISER, Pune

Title:

On-surface molecular doping – a nanoscale perspective

Date:

4th Jan (Fri), 2019

Time:

11:30 AM (Tea at 11:20 AM)

Venue:

FB 382(Prof. Amal Raychaudhuri Seminar Room)

Abstract:

Molecular assembly on a surface presents a rich testbed to probe intermolecular interactions and molecule-surface interactions. Such interactions are pertinent to understand the characteristics of the molecules and their host surfaces, which can then be tuned for applications. In this talk I will present a study of phthalocyanine (Pc) molecules on the noble metal surface - Au(111) and topological insulator surface (TI) - Bi2Se3 , using low temperature scanning tunneling microscopy (STM) and spectroscopy (STS). Starting with copper phthalocyanine – CuPc and its cyano analogue – CuPc(CN)8 we observe the self-assembly characterized by an organizational chirality for both these molecules on Au(111). Superimposed on this is an orbital-energy-dependent chirality seen only in the case of CuPc(CN)8. STS measurements show an increment in the highest occupied–lowest unoccupied molecular orbital (HOMO–LUMO) gap from CuPc to CuPc(CN)8. For Bi2Se3, CuPc shows a peculiar self-assembly along with single CuPc adsorption. STS measurements show a shift of the Dirac point for this system that indicates charge transfer at the molecule-TI interface. For the magnetic iron phthalocyanine – FePc, its adsorption on Bi2Se3 keeps the Dirac point intact indicating that the topological surface state remains protected. These findings have led to a better molecular scale picture of adsorption, self-assembly, and electronic properties along with emergent properties specific to molecule-TI hybrid interfaces.


Speaker:

Subhasish Mandal

Affiliation:

Department of Physics & Astronomy, Rutgers University, New Jersey (USA)

Title:

First principles investigation on quantum materials

Date:

24th December, 2018(Monday)

Time:

11:00 AM (tea @ 10:45AM)

Venue:

FB 382(Prof. Amal Raychaudhuri Seminar Room)

Abstract:

Computer simulations based on first principles calculations play a central role in helping us understand, predict, and engineer physical, chemical, and electronic properties of technologically relevant materials. This can solve many problems towards building faster, smaller and cheaper devices for processing and storing information as well as for saving energy. Many of these processes involve electron excitations and strong local magnetic fluctuation that the ‘standard model’ of electronic structure, Density Functional Theory (DFT), can’t capture properly. In this context, I will highlight my work in two popular approaches that go beyond the standard DFT. Dynamical Mean Field Theory (DMFT) in combination with DFT has recently been successful for detailed modeling of the electronic structure of many complex materials with strong electron correlation. To give an example, I will show the anomalous properties of the iron-based superconductors in both bulk and monolayer phases, which have their origin in strong Hund's coupling [1]. In this context, I will discuss how computed electron-phonon coupling could be enhanced in the presence of electron correlation in FeSe. This has been recently verified in a femto-second coherent locked-in photoemission spectroscopy experiment [2,3]. Another ab-initio method that goes beyond the limit of DFT is GW-approximation, which is extensively used to compute excited states of electrons in solids. So far, most of the GW calculations have been confined to small unit-cell of bulk-like materials due to the extreme computational demand of the approach. I will discuss my collaborative effort toward developing a high scalable, open-source GW software to compute electronic excited states more efficiently for petascale architectures using the Charm++ parallel framework [4,5]. At the end, I will briefly discuss topological crystalline insulators, which are a new class of topological materials where electronic surface states are topologically protected along certain crystallographic directions by crystal symmetry. I will discuss how without any external perturbation, both massless Dirac fermions protected by the crystal symmetry and massive Dirac fermions with crystal symmetry breaking can coexist on a single surface [6].

References:

1. S. Mandal, P. Zhang, S. Ismail-Beigi, K. Haule; “How correlated is the FeSe/SrTiO3 system?”. Phys. Rev. Lett. 119, 067004 (2017).
2. S. Mandal, R. E. Cohen, and K. Haule; “Strong Pressure Dependent Electron-Phonon Coupling in FeSe”. Phys. Rev. B Rapid Communications 89, 220502(R) (2014).
3. S. Gerber et al.; “Femtosecond electron-phonon lock-in by photoemission and x-ray free-electron laser” Science 357, 71 (2017).
4. M. Kim*. S. Mandal* et al. “Scalable GW software for quasiparticle properties using OpenAtom” arXiv:1810.07772 (2018).
5. http://charm.cs.illinois.edu/OpenAtom/
6. O. E. Dagdeviren*, S. Mandal* et al. Phys. Rev. Mat. 2, 114205, (2018).


Speaker:

Ashild Fredriksen

Affiliation:

Department of Physics and Technology, UiT The Arctic University of Norway

Title:

Energetic electrons near a current-free double layer in inductively coupled helicon plasma

Date:

18th December,2018(Tuesday)

Time:

4:00pm (tea @ 3:45pm)

Venue:

FB 382(Prof. Amal Raychaudhuri Seminar Room)

Biosketch:

Ashild Fredriksen is a Professor in the Department of Physics and Technology at UiT The Arctic University of Norway. Her research interests include experimental plasma physics, acceleration and heating processes, current free double layers, turbulence and turbulent structures, plasma diagnostics and ion beams.

Abstract:

In inductively coupled helicon sources, current-free double layers (CFDL) can be formed self-consistently without external current forcing. The CFDLs are evidenced by an ion beam formed as a result of a potential drop between the upstream plasma source and the downstream diffusion chamber. The electrons in the double layer play an important role in balancing the ion beam current, but apart from some observations of electron energy probability functions (EEPFs) by means of Langmuir probes (K. Takahashi et al., Appl. Phys. Lett., 94, 191503 (2009)) little information has previously been obtained about the electron population in the up- and downstream regions near the CFDL.
An inverted retarding field energy analyzer (RFEA), is an ion energy analyzer biased to measure electrons instead. With this setup we measured for the first time the high-energy part of the electron distribution along the radial direction in the diffusion chamber. We found a prominent peak of high-energy electrons up to 60 eV at the footprint of the magnetic field lines emerging from the layer near the wall of the source. This coincides with increased electron temperatures and ion densities at this position. Another small but significant distribution of electrons at energies more than 100 eV are observed within the region of the ion beam itself. Later, such measurements have been performed in the source, also here with some evidence of energetic electrons.


Speaker:

Ujjal K. Dey

Affiliation:

APCTP Pohang, South Korea

Title:

Light dark matter through assisted annihilation

Date:

23rd October(Tuesday)

Time:

4:00pm (tea @ 3:45pm)

Venue:

FB 382(Prof. Amal Raychaudhuri Seminar Room)

Abstract:

Recent observations from direct detection experiments put stringent constraints on the popular WIMP cold dark matter (DM) models. Moreover, there are cosmological observations from the galactic scale structure formation which suggests the DM should be self-interacting and light -- the fact which is not in consonance with the WIMP paradigm. In this talk we will focus on the light dark matter scenarios where annihilation to Standard Model particles at tree-level may be kinematically forbidden. In such cases annihilation can be aided by massive Standard Model-like species, called assisters, in the initial state that enhances the available phase space opening up novel tree-level processes. We will then discuss the feasibility of such non-standard assisted annihilation processes to reproduce the observed relic density of dark matter and implications from direct detection. Finally, we shall talk about the future prospects of such DM scenarios.


Speaker:

Venkata S. Bhadram

Affiliation:

Carnegie Institute of Science, Washington D.C.

Title:

Matter under Extreme Pressures: A Route to Discover Metastable Materials

Date:

24th September, 2018

Time:

11:00 AM(Tea at 10:50 AM)

Venue:

FB 382(Prof. Amal Raychaudhuri Seminar Room)

Abstract:

The ongoing technological advances demand the need for discovering new materials with intriguing properties. The oft-overlooked arena of metastable phases may yield promising new technological materials. [1-3] The metastable phases of materials are not the ground states at room conditions but can be accessed and stabilized using extreme environments, notably high-pressures and temperatures.[4,5] In my talk, I would present the discovery of two such metastable phases in Ti-N system, 1) TiN2, which is a promising superhard material that contains unique nitrogen subunits with highly energetic N―N single bonds [6] 2) Ti3N4, which is the first semiconducting titanium nitride known to date.[7] Although, these compounds possess positive enthalpies (thermodynamically unstable) at room conditions, high-pressure/temperature conditions made it possible to access and stabilize these phases. The strategy that we employed by marrying first principles theoretical calculations to high-pressure synthetic techniques to synthesize and characterize these materials is an unique approach towards discovering novel high-density and high-energy structures (metastable phases) of materials which are otherwise very difficult to be accessed. I would also talk about our efforts to stabilize photoresponsive solid solutions of zinc and manganese oxides in metastable rocksalt phase.[8] These phase-pure, chemically homogeneous and thermally stable (up to 500°C) novel solid-solutions exhibit moderate photocurrents when tested for solar light harvesting applications. Apart from photoresponse, these solid solutions exhibit interesting magnetic phase transition and field dependent magnetic behavior at low-temperatures.
References:
1)W. Sun et al, Science Advances, 2, 1 (2016).
2)D. Y. Kim et al, Nature Materials, 14, 169 (2015).
3)B. Keimer, J. E. Moore, Nature Physics, 13, 1045 (2017).
4)V. V. Brazhkin, “High-Pressure Synthesized Materials: Treasures and Hints” High Pressure Research, 27, 333 (2007).
5)W. Sun et al, Thermodynamic Routes to Novel Metastable Nitrogen-Rich Nitrides, Chemistry of Materials, 29, 6936 (2017).
6)V. S. Bhadram, D. Y. Kim and T. A. Strobel. “High-Pressure Synthesis and Characterization of Titanium Pernitride.” Chemistry of Materials, 28, 1616 (2016).
7)V. S. Bhadram, H. Liu, E. Xu, T. Li, T. A. Strobel, “Semiconducting Cubic Titanium Nitride in the Th3P4 structure.” Physical Review Materials, 2, 011602 (R) (2018).
8)V. S. Bhadram, Q. Cheng, C. K. Chan, Y. Liu, K. Landskron, and T. A. Strobel, “ZnxMn1-xO Solid Solutions in the Rocksalt Structure: Optical, Charge-Transport and Photoelectrochemical Properties. ACS Applied Energy Materials, 1, 260 (2018).


Speaker:

Dr. K.R. Koteswara

Affiliation:

Technische Universitaet Dortmund, Germany

Title:

Quantum Information Processing and Hyperpolarization of nuclear spins using Nitrogen-Vacancy centers in diamond

Date:

13th September, 2018

Time:

11:00 AM(Tea at 10:50 AM)

Venue:

FB 382(Prof. Amal Raychaudhuri Seminar Room)

Abstract:

Nitrogen-Vacancy (NV) centers in diamond have interesting properties for a number of quantum technologiesincluding quantum information processing and nano-scale Nuclear Magnetic Resonance (NMR). In this presentation, I will talk about our recent experimental research on NV centers for the applications of quantum information processing and hyperpolarization of nuclear spins.I will first introduce NV centers, their properties and some of their applications. Then, I will talk about interactions between single electron spins of NV centers and proximal nuclear spins and interesting level anti-crossings that occur because of these interactions. Some of the interesting results of this analysis are (i) dynamics of a single-spin driven beyond the rotating-wave approximation and (ii) decoherence-free subspaces. Next, I will talk about transferring polarization of optically pumped NV centers to bulk 13C nuclear spins of the diamond lattice. Finally, I will discuss strategies to realize scalable quantum information processing using NV centers and transferring polarization of optically pumped NV centers to nuclear spins outside the diamond surface.


Speaker:

Ish Dhand

Affiliation:

Ulm University, Ulm, Germany

Title:

Proposal for Quantum Simulation via All-Optically Generated Tensor Network States

Date:

4th September, 2018

Time:

04:00 PM(Tea at 3:45 PM)

Venue:

FB 382(Prof. Amal Raychaudhuri Seminar Room)

Abstract:

We devise an all-optical scheme for the generation of entangled multimode photonic states encoded in temporal modes of light. The scheme employs a nonlinear down-conversion process in an optical loop to generate one- and higher-dimensional tensor network states of light. We illustrate the principle with the generation of two different classes of entangled tensor network states and report on a variational algorithm to simulate the ground-state physics of many-body systems. We demonstrate that state-of-the-art optical devices are capable of determining the ground-state properties of the spin-1/2 Heisenberg model. Finally, implementations of the scheme are demonstrated to be robust against realistic losses and mode mismatch.


Speaker:

Dr. Vishwanath Shukla

Affiliation:

Post-Doc, L'Institut de Physique de Nice (INPHYNI), Université Côte d’Azur, Nice, France.

Title:

Collisions of active particles in quantum fluids and quantitative estimation of effective viscosity in quantum turbulence

Date:

30th August, 2018

Time:

04:00 PM(Tea at 3:45 PM)

Venue:

FB 382(Prof. Amal Raychaudhuri Seminar Room)

Abstract:

Particles of low velocity, traveling without dissipation in a superfluid, can interact and emit sound when they collide. We propose a minimal model in which the equations of motion of the particles, including a short-range repulsive force, are self-consistently coupled with the Gross-Pitaevskii equation. We use this model to demonstrate the existence of an effective superfluid-mediated attractive interaction between the particles; and we study numerically the collisional dynamics of particles as a function of their incident kinetic energy and the length-scale of the repulsive force. We find a transition from almost elastic to completely inelastic (sticking) collisions as the parameters are tuned. We find that aggregation and clustering result from this sticking transition in multi-particle systems. We also report our recent results on the decay of three-dimensional quantum turbulence at finite temperatures and provide a quantitative estimation of effective viscosity at finite temperatures.


Speaker:

Dr. Sourabh Lahiri

Affiliation:

BIT Mesra, Ranchi

Title:

Some aspects of Stochastic Thermodynamics and Quantum Random Walk

Date:

27th August, 2018

Time:

04:00 PM(Tea at 3:45 PM)

Venue:

FB 382(Prof. Amal Raychaudhuri Seminar Room)

Abstract:

The talk would be divided into two parts. In the first half, I will provide a pedagogical introduction to Stochastic Thermodynamics (i.e., Thermodynamics applicable to systems at mesoscopic scales), followed by stating a few results that we have contributed to. The second half would involve the description of a quantum particle evolving under tight-binding Hamiltonian on a one-dimensional lattice having a detector at the origin. A method of computing the survival probability and the first detection time probability would be discussed.


Speaker:

Sathyanarayana Paladugu

Affiliation:

Kent State University

Title:

Tunable Electrophoresis of Colloids in Liquid Crystalline Electrolytes

Date:

23th August, 2018

Time:

11:00 AM (Tea at 10:50 AM)

Venue:

FB 382(Prof. Amal Raychaudhuri Seminar Room)

Abstract:

Electokinetics in colloidal systems represents a broad and interesting class of out-of-equilibrium effects, caused by the external electric field that acts on spatially separated charges. Usually, the colloids are dispersed in an isotropic electrolyte such as water. In this seminar, first we discuss about many-body effects for the critical Casimir forces emerging in the presence of several colloidal particles within a critical mixture of water and 2,6-lutidine. Critical Casimir forces emerge on objects immersed in binary liquid mixtures kept near their critical (demixing) points due to the confinement of the spatial fluctuation of the local mixture composition. By taking advantage of a spatial light modulator (SLM), we generate multiple reconfigurable holographic optical tweezers (HOTs) which permit to optically trap several colloids. The forces acting on them are then determined via digital video microscopy. We first study the critical Casimir force arising between two particles as a function of their distance and then we investigate how this is affected by the presence of a third neighbouring particle. Later we discuss novel features of the dynamic out-of-equilibrium behavior of colloids when the disperse medium is an anisotropic electrolyte, namely, a nematic liquid crystal. Because of orientational order, nematics show anisotropy of properties such as electric conductivity and dielectric permittivity. When the electric field is applied to a nematic with a director that varies in space, anisotropy causes the ionic charges to separate in space. The density of space charge is proportional to the applied field, director gradients, anisotropy of conductivity and permittivity. In other words, separation of charges is defined by the properties of the liquid crystal electrolyte rather than by the properties of the solid component as in the case of isotropic electrolytes. The separated charges move in the electric field, creating electro-osmotic or electrophoretic effects with velocities proportional to the square of the electric field. We use nematic cells with photopatterned director field to illustrate the principle of the liquid crystal-enabled electrokinetics and its advantages, such as steady character of flows, control of vorticity, and the ability to transport colloidal particles of any type (solid, liquid, gaseous). We also demonstrate that the colloidal particles can be electrophoretically active even in a uniform nematic cell, provided their surface induces local dipole-like director distortions. Such a particle will move even if the electric conductivity is isotropic, being supported solely by the dielectric anisotropy. We demonstrate that the change in the sign of anisotropy causes reversal of the particle motion. Finally, we also demonstrate that the electric field can produce particle-like propagating solitary waves representing self-trapped “bullets” of oscillating molecular director. These director bullets lack fore-aft symmetry and move with very high speed perpendicularly to the electric field and to the initial alignment direction. The bullets are true solitons that preserve spatially confined shapes and survive collisions.


Speaker:

Dr. Juzar Thingna

Affiliation:

University of Luxembourg, Luxembourg

Title:

Nonequilibrium statistical physics: A master equation perspective

Date:

20th August, 2018

Time:

04:00 PM (Tea at 3:45 PM)

Venue:

FB 382(Prof. Amal Raychaudhuri Seminar Room)

Abstract:

I will give in this talk a basic overview of the key concepts in nonequilibrium statistical physics and its connections to the theory of classical and quantum open systems described via master equations. In the first part of the talk, I’ll discuss the basics of the theory of open systems and its historical sources that can be traced back to Pauli (1928), Lindblad (1976), and others. I’ll also describe the thermodynamic framework that forms a super structure on the master equations and can be applied to systems in equilibrium and nonequilibrium. In the second part, I will briefly talk about some of the recent advances in the theory of open systems, taking three examples: i. Beyond weak system-reservoir coupling, ii. Large synchronizing networks, and iii. Finite reservoirs, and its consequences on the nonequilibrium thermodynamics.


Speaker:

Dr. Jayita Nayak

Affiliation:

University of California Davis, USA

Title:

Electronic structure of topological materials and quasicrystals

Date:

7th August (Tuesday), 2018

Time:

11:00 AM (Tea at 10:50 AM)

Venue:

FB 382(Prof. Amal Raychaudhuri seminar room)

Abstract:

The discovery of topological materials has created tremendous attention in the scientific community and beyond because these materials can exhibit a novel state of matter in which topologically protected gapless states on their edges or surfaces are present. Such states are protected from scattering by impurities and thus have important technological applications. The rare-earth monopnictide LaBi, LaSb exhibits very large, unusual magnetoresistance which stimulates the interest in directly observing any topological surface states. Although band inversions have been postulated to induce a topological phase in LaBi but there was no experimental evidence for topological surface states in this compound. By using angle-resolved photoemission spectroscopy (ARPES) and ab-initio calculations, we have revealed the existence of topological surface states of LaBi through the observation of three Dirac cones: two coexist at the corners and one appears at the centre of the Brillouin zone. The odd number of surface Dirac cones is a direct proof of the topological nature of LaBi compound. Moreover, our ARPES measurement in conjugation with band structure calculation established the Type II Dirac semi metallic phase in PtSe2. In my recent work, six fold degeneracy has been observed at the crossing point in PdSb2 compound in contrast to Dirac and Weyl semimetals. We have used hard x-ray photoelectron spectroscopy (HAXPES) to investigate the bulk electronic structure of quasicrystals to resolve the controversy about the existence of pseudogap in these materials. The near Fermi edge (EF) spectra of Al-Pd-Mn as well as Al-Cu-Fe are strongly suppressed in intensity at EF, which provides strong evidence for the existence of the pseudogap in contrast to surface sensitive low energy photoemission spectra that shows a metallic Fermi edge. From fitting of the spectra by inverted Lorenzian function the evidence of fully formed pseudogap in Al-Cu-Fe demonstrate that the DOS at EF is zero indicating that it is close to a metal-insulator phase boundary. The existence of deeper pseudogap in bulk has been supported by the theoretical calculations. On the other hand, the HAXPES near EF spectrum of both Zn-Mg-Dy and Zn-Mg-Y exhibits shallower pseudogap compared to the Al based quasicrystals (Al-Pd-Mn and Al-Cu-Fe) that may be related to their larger carrier concentration compared to Al-Pd-Mn.


Speaker:

Dr. Debabrata Mishra

Affiliation:

Department of Physics & Astrophysics, University of Delhi

Title:

General Physics Seminar: Chirality Induced spin selectivity in electron transmission through self-assembled monolayers of biomolecules and its applications

Date:

29th September (Thursday), 2016

Time:

2:30 PM

Venue:

FB 382

Abstract:

In a ground breaking discovery at Weizmann Institute of Science, we have found that electrons, transmitted through helical (chiral) protein, DNA and peptides, yield spin polarized electron (up to 64% for DNA) due to the lack of inversion symmetry associated with the chiral (DNA) molecules. ‘Chirality’ in molecular systems represents structural asymmetry in which one enantiomer has “right handed” symmetry and the other “left handed”. The interaction of circularly polarized light, magnetic field or spin-polarized electrons with this chiral potential varies for the specific enantiomer and gives exciting results. I will present the discovery and development of chirality induced spin selectivity effect of self-assembled monolayers made from molecules having a helical structure, like protein (bacteriorhodopsin), dsDNA and oligopeptides of different molecular length adsorbed on Au, Ni and Al thin films. Our results indicate that helical structure promotes electron transmission and efficient spin filtering at room temperature. Interestingly, this effect could be exploited to see the spin dependent photoluminescence behavior induced by chiral protein in a hybrid semiconductor quantum dot-Protein thin film. I will also briefly discuss on some of the exciting results on spin specific chemical reactions induced by chiral dsDNA and my future research plan.


Speaker:

Professor Sanjoy Biswas

Affiliation:

Korea Institute for Advance Study

Title:

General Physics Seminar: Closing in on the Standard Model like Higgs boson

Date:

1st March (Tuesday)

Time:

4:00 PM

Venue:

FB 382

Abstract:

The Large Hadron Collider Experiment at the CERN has discovered a Higgs-like resonance. However, the confirmation of any resemblance with the Standard Model Higgs boson requires a precise measurements of its properties and couplings with the Standard Model particles. In addition, it is also important to look for any hint of New Physics that might be associated with its production and/or decay. In this talk, I will shed some light on some of these issues.


Speaker:

Dr. Tanmoy Mondal

Title:

Vacuum stability and unitarity in Left-Right Symmetric Model

Date:

25th Feb, 2016

Time:

3:00 PM

Venue:

FB 382

Abstract:

Left-Right symmetric models are very appealing as BSM scenarios. In this talk I will discuss how theoretical constrains can be useful to restrict the LR model. Using copositivity we computed the criteria which guarantee that the vacuum is bounded from below in all directions. We examine the usefulness of the unitarity conditions which can translate into giving a stronger constraint on the model parameters together with the criteria derived from vacuum stability and perturbativity. In this light, we demonstrate the bounds on the masses of the physical scalars present in the model and find the scenario where multiple scalar modes are in the reach of Large Hadron Collider.


Speaker:

Professor Sei Suzuki

Affiliation:

Department of Liberal Arts Saitama Medical University Moroyama, Saitama 350-0495, Japan

Title:

Dynamics of decoherence of a qubit coupled to a spin-chain environment

Date:

24th Feb, 2016

Time:

3:00 PM

Venue:

FB 382

Abstract:

Decoherence of a quantum system is one of the important issues in quantum computation and quantum information. Controlling decoherence has been discussed recently in NMR or cold atomic experiments. We study the time dependence of the decoherence of a single spin interacting with a spin-chain environment. When the environment is close to a quantum critical point, the decoherence of a system may show a time dependence characteristic to the universality of the associated quantum critical point. In the seminar, we shall present a universal scaling theory of decoherence of a single spin when the system-environment coupling is week and the environment is slowly varied with time across a quantum critical point.


Speaker:

Mr. Atanu Rajak

Affiliation:

Saha Institute of Nuclear Physics, Kolkata

Title:

Statics and dynamics of topologically ordered and quenched disordered quantum many body systems

Date:

25th February 2016 (Thursday)

Time:

4:00 PM ( Tea will be served at 3:45 PM)

Venue:

FB 382

Abstract:

Given the recent interest in the non-equilibrium quenching dynamics of quantum many-body systems across quantum critical points (QCPs), the studies involving quenching dynamics of a topological system across a QCP have emerged as a rapidly growing field of research. Especially, the quenching dynamics of a topological insulator and the p-wave superconductors have been explored in this connection. In the first part of this talk, I will discuss the dynamics of a Majorana edge mode in a p-wave superconducting chain following sudden and slow changes of a parameter of the Hamiltonian across QCPs. The survival probability of an edge Majorana as a function of time is studied when the system is suddenly driven from one topological phase to the other and also to the QCPs separating these phases. In the context of slow quenching dynamics of a finite p-wave superconducting chain with a complex hopping term, we ask the question whether an edge Majorana can be transported from one topological phase to the other across a gapless region. While an extensively studied NP-hard search problem of the ground state is that of the Sherrington-Kirkpatrick (SK) model. In the next part, I will speak on an interesting result that the crossover between classical (thermal) and quantum fluctuation dominated critical behaviors for the SK spin glass in transverse field occurs at a non-vanishing temperature.


Speaker:

Professor Janusz Gluza

Affiliation:

Institute of Physics, Katowice Poland

Title:

High Energy Physics Seminar: Techniques and tools for loop calculations. Mellin-Barnes integrals, the AMBRE package

Date:

22. 02. 2016 ( Monday)

Time:

4:00 PM ( Tea will be served at 3:45 PM)

Venue:

FB 382

Abstract:

I will shortly summarize methods and software used in precise multi-loop calculations. Then I will discuss pros and cons of the Mellin-Barnes method. I will demonstrate on a couple of running examples how to use the Mathematica package AMBRE/MB (for the files see: http://prac.us.edu.pl/~gluza/ambre/).


Speaker:

Dr. Mayukh Ray

Affiliation:

Saha Institute of Nuclear Physics, Kolkata

Title:

CONDENSED MATTER PHYSICS SEMINAR: Influence of Martensite Transformation on the Magnetic and Transport Properties of Ni-Mn based Heusler Alloys

Date:

9th February, 2016 (Tuesday)

Time:

11:00 AM, Tea at 10:50 AM

Venue:

FB 382 (Physics Seminar Room)

Abstract:

The striking applicable properties and complex magnetism of Ni-Mn based Heusler alloys are mainly arises due to the first order martensite transformation (MT). Thus, it is necessary to understand the influencing factors [1]. The magnetic ground state of this dense magnetic type system giving rise to cluster spins glass state apart from its re-entrant spin glass behaviour. We will discuss it on the context of d.c and a.c magnetization and low temperature specific heat measurements [2]. The high field cooling through the irreversibility temperature finds more significant effect on the thermo-remanent magnetization (TRM) of martensite phase than the system cooled only through its martensite transformation (MT) [3]. This observation cannot be explained using the theory of kinetic arrest for first order transition. How one can induce a ferromagnetic austenite phase in place of paramagnetic austenite phase without altering the magnetic behaviour of low temperature martensite phase. I will also discuss how the martensite and austenite phase fraction across the MT influence the magneto-resistance when a magnetic field is applied. The origin of giant magneto-resistance across the MT will also be discussed [4]. References 1. Ray et al. J. Appl. Phys. 114, 123904 (2013). 2. Ray et al. Euro. Phys. Lett. 109, 47006 (2015). 3. Ray et al. J. Magn. Magn. Mater. 396, 26 (2015). 4. Ray et al. J. Phys. D: Appl. Phys. 47, 385001 (2014).


Speaker:

Dr. K. S. Narain

Affiliation:

Abdus Salam International Center for Theoretical Physics, ASICTP, Trieste, Italy

Title:

High Energy Physics Seminar : Physical string realization of Walcher's Topological string

Date:

08. 02. 2016 (Monday)

Time:

4:00 PM ( Tea will be served at 3:45 PM)

Venue:

FB 382


Speaker:

Dr. U. Chandni

Affiliation:

California Institute of Technology, USA

Title:

General Physics Seminar: Engineering quantum transport in low dimensional electron systems

Date:

1st February (Monday) 2016

Time:

11:0 AM, Tea at 10:50 PM

Venue:

FB 382 (Physics Seminar Room)

Abstract:

When electron systems are constrained to low dimensions, interactions can lead to exciting many body physics and broken symmetry states, exhibiting topological order and emergent behavior. In this talk, I will discuss electron transport in nanoscale structures consisting of two dimensional (2D) layered materials as well as one dimensional metallic nanowires. Firstly, I will discuss our efforts to engineer spin-orbit effects in graphene. This was spurred by recent theoretical predictions that heavy metal adatoms such as Indium can introduce spin-orbit coupling in graphene and lead to topological states of matter. In the second part of the talk, I will discuss our ongoing efforts in understanding electron tunneling in Van der Waals heterostructures. We employ atomically thin layers of hexagonal boron nitride as the insulating layer and metals or graphite/graphene as the counter-electrodes. Our results show strong evidence for phonon and defect mediated tunneling in such heterostructures. I will also briefly describe some of our earlier experiments on transport in ultrathin gold nanowires. We observe tunability between a non-Fermi Luttinger liquid state and a disordered state exhibiting hopping transport. In the end, I will present how these efforts can be expanded to create heterostructures of 1D and 2D materials to further explore spintronics, straintronics, tunneling and spin-orbit interactions among other phenomena.


Speaker:

Dr. Ishan Talukdar

Affiliation:

University of California, Berkley CA, USA

Title:

Trapped ions for quantum information processing

Date:

1 February, 2015

Time:

4:00 PM (Tea at 3.45 pm)

Venue:

FB 382 (Physics conference room)

Abstract:

Laser-cooled and electromagnetically confined ions offer a quantum information processing platform with a great degree of coherence and tunability. In order to utilize such a system to solve classically hard problems, scaling to a larger computational manifold is necessary. Microfabricated surface traps promise scalability, however bringing along a new set of challenges. In this talk, after an introduction to this technology, I will discuss our efforts in understanding and tackling a source of anomalous noise in surface traps which can compromise fidelities of quantum gate operations.


Speaker:

Dr. Ketan Patel

Affiliation:

IISER Mohali

Title:

Anarchic Yukawas in Higher Dimensional Theories

Date:

28th January (Thursday)

Time:

4 pm

Venue:

FB 382

Abstract:

Can very special pattern of fermion masses be obtained without a symmetry principle? I will try to address this question in a higher spacetime dimensional framework. An extra-dimension compactified on an orbifold generates different zero-mode profiles for fermions of different charges. Utilizing suitable scalar fields, a predictive model for fermion masses and mixing is constructed and shown to be viable with the current data. All the Yukawa couplings in the model are of order unity while the hierarchies among different fermions result from the wave-function profiles. The naturalness of anarchical Yukawa couplings and predictions for various experimentally observable parameters will be discussed.


Speaker:

Dr. Kush Saha

Affiliation:

University of California, Irvine

Title:

TPSC Seminar series: Interplay between electronic band topology and phonons in Dirac materials

Date:

11th January, 2016 (Monday)

Time:

4-5 PM (Tea 3.45 PM onwards)

Venue:

FB 382

Abstract:

In this talk, I will discuss topological phase transition in intrinsically nontopological materials. In particular, I will show that electron-phonon interactions can induce topological phases in direct and narrow-gap Dirac insulators. The underlying mechanism for this effect can be explained in terms of the electron-phonon scattering matrix elements, which show a peculiar dependence on the sign of the mass of the Dirac fermions. A similar mechanism applies to weak Coulomb interactions and spin-independent disorder; however, the influence of these on band topology is largely independent of temperature. Finally, I will discuss the inverse of the above effect, concerning back action of the electronic band topology on the phonons. In particular, I will show that phonon linewidth may help detect the topology of the electronic bands. The underlying mechanism can again be attributed to the electron-phonon matrix elements as mentioned before.


Speaker:

Dr. Samir Kumar Biswas

Affiliation:

IIT, Hyderabad

Title:

Developing opto-acoustic based diagnostic devices: theory, design, optimization and patient measurement

Date:

11th January, 2016 (Monday)

Time:

4 pm

Venue:

SL215 (CELP seminar room)

Abstract:

Light and ultrasound transport through living tissue has been the focus of recent research in biophysics and bioengineering, mainly due to its potential application in non-destructive non-invasive diagnostic pathology. Using soft radiation like light and ultrasound, the tissue activities such as metabolism, blood flow in tissue can be quantified by correlating them with chromophores (haemoglobin, melanin, water, lipid etc). My talk will be the physics of soft matter under non-ionized radiation for tissue parameter extraction where light-tissue and ultrasound-tissue interaction will be modelled with second order partial differential equation. With advanced mathematics, physics of light and acoustic, the angiogenesis in human subjects and rat brain over a virtual domain will be reconstructed to understand the neurological problem, inflammation, arthritis progress in human inflamed joints and other possibilities such as melanoma in skin, lymph nodes inflammation etc will be the matter of discussion.


   

Speaker:

D.Venkateswarlu

Affiliation:

UGC-DAE Consortium for Scientific Research, Indore

Title:

Superconductivity in Oxy-nitrides and Skutterudites

Date:

6th January 2016 (Wednesday)

Time:

11 am

Venue:

FB-382

Abstract:

Resistive broadening of Niobium Oxy-nitride samples is studied in terms of Aslamazov and Larkin (AL) theory &Lowest Landau Level (LLL) scaling for data collected down to 2K and fields upto 14T. The fluctuation dimensionality of the system is estimated from the analysis apart from other interesting parameters of interest like Ginzburg number, coherence length etc. The magnetic field induced broadening has been analysed in the TAFF (Thermally Activated Flux Flow) formalism. The activation energies of flux linesare obtained that shows a collective pinning scenario at higher magnetic fields. At low temperatures and high enough magnetic fields, a vortex glass state is observed in Niobium Oxy-nitride samples and the relevant parameters of interest are discussed. Skutterudites are relatively a new family of thermoelectric materials having promising thermoelectric properties especially due to the rattling like motion of filler atoms. The ground state of such materials is quite interesting as many of them are quite unconventional. Superconductivity in these systems is so because of the interplay between pairing and magnetism in these materials. A case study of PrPt4Ge12shows that there is a survival and existence of superconducting energy gap even after the removal of Pr down to 50 at % in PrPt4Ge12, that prelude the existence of superconductivity in an otherwise Pt4Ge12 cage as predicted by theory. Pr acts as the main stabilizing agent. A point-nodal to node-less evolution of superconducting energy gap is shown to exist as a function of Nd co-doping with Pr (up to 0.3) in Pr1-xNdxPt4Ge12 using heat capacity.


   

Speaker:

Dr Arun M. Thalapillil

Affiliation:

Department of Physics and Astronomy Rutgers, The State University of New Jersey

Title:

Probing New Physics at the LHC, Future Colliders & Yonder…

Date:

5th January (Tuesday) 2016

Time:

4 PM

Venue:

FB-382

Abstract:

The discovery of the Higgs boson has opened up new avenues to probe for physics beyond the standard model, and motivates us to revisit aspects of various models in this new light. In this talk I would like to briefly discuss three topics influenced by this - searches at the LHC & future PP-colliders for SM gauge singlet states that couple to the Higgs; supersymmetric, radiatively-generated fermion masses in the context of Higgs-fermion couplings and the muon anomalous magnetic moment; and lastly, flavor constraints on extended gauge mediation models, that accommodate large A-terms.


   

Speaker:

Dr Arun M. Thalapillil

Affiliation:

Department of Physics and Astronomy Rutgers, The State University of New Jersey

Title:

Here be Dragons - The Coming Era of Discovery at the LHC & Beyond…

Date:

4th January (Monday) 2016

Time:

4 PM

Venue:

FB-382

Abstract:

A new era has already begun with the advent of the Large Hadron Collider (LHC). Other collider and non-collider experiments, either currently running or planned for the near future, promise to shed light on some of the most intriguing questions in physics today - are there new symmetries of nature, what comprises dark matter, why is there a matter anti-matter asymmetry, what is the origin of fermion masses and so on. The Higgs boson, an excitation of the field responsible for electroweak symmetry breaking and the origin of mass, has already been discovered. A similar era of investigation into uncharted territory, at the frontier, has not existed in many decades! In this talk, I would like to briefly discuss how some of the experimental discoveries and programs specifically relating to the Higgs-like resonance have opened up new avenues, to probe and think about new physics.


   

Speaker:

Dr. Pradipta Ghosh

Affiliation:

Laboratoire de Physique Théorique, Orsay Université de Paris-Sud

Title:

Light singlets in supersymmetry: A glimpse beyond the Standard Model

Date:

15th December, Tuesday

Time:

4 PM

Venue:

FB-382

Abstract:

Supersymmetry is a well-motivated extension beyond the standard model to overpower its shortcomings. Certain supersymmetric models contain non-minimal field content. These models can easily accommodate light neutral scalar(s) and fermion(s) in the spectrum. These light states have different novel phenomenological implications, e.g., producing unusual decay modes for the heavier standard model particles, like W ± , Z and Higgs. An analysis of this kind is a viable alternative to probe physics beyond the standard model even when rest of the mass spectrum remains beyond the reach of the LHC. We exemplify our analysis for two non-minimal supersymmetric models with singlet superfields.


   

Speaker:

Dr. Pradipta Ghosh

Affiliation:

Laboratoire de Physique Théorique, Orsay, France

Title:

When Neutrinos meet the Collider

Date:

10th December (Thursday)

Time:

3:30 PM

Venue:

FB-382

Abstract:

Experimental detection of neutrino oscillation provides firm evidence of physics beyond the standard model. Some of these new theories predict intriguing correlations between a few collider observables and the neutrino mixing angles. Measurements of these collider observables are highly envisaged during run-II of the LHC with upgraded configurations. We investigate complementary aspects of the collider and neutrino physics experiments through these correlations. We show how one can utilise these correlations to discriminate different new physics scenario.


   

Speaker:

Dr. Arijit Kundu

Affiliation:

Technion, Israel

Title:

Non-trivial Transport in Floquet Topological Insulators

Date:

26th November 2015 (Thursday)

Time:

4.00 PM

Venue:

FB-382

Abstract:

Floquet topological insulators are characterized by invariant, called Bott indices, which have no equilibrium analogue. Systems with non-vanishing Bott indices may give rise to counter-intuitive transport phenomena, especially in a disordered system. For instance, the disorder can enhance the transport, in presence of certain lattice symmetry. Whereas, in certain highly disordered Floquet topological insulator, quantized charge transport can take place through edge states, where the bulk behaves as an Anderson insulator.


   

Speaker:

Dr. Arijit Kundu

Affiliation:

Technion, Israel

Title:

Topology and Transport in Periodically Driven Systems

Date:

24th November 2015 (Tuesday)

Time:

4.00 PM

Venue:

FB-382

Abstract:

Topological systems in condensed matter are characterized by quantities which can only be measured non-locally. One way to introduce topological phases in certain systems is periodic driving. For example, an 1D p-wave superconductor, when driven periodically, becomes topologically non-trivial and hosts exotic steady states, which are called Floquet Majorana fermions. Whereas, graphene, under the application of circularly polarized laser is an example of Floquet topological insulator. Such topological insulators, like the quantum-hall systems, have non-trivial topology and chiral edge states which give rise to novel transport characteristics which are unique to the time-periodic systems. These systems present potential applications to various fields from quantum computation to valleytronics.


   

Speaker:

Dr. Panchanana Khuntia

Affiliation:

Laboratoire de Physique des Solides, Universit´e Paris-Sud 11, UMR CNRS, 91405 Orsay, France

Title:

NMR as a Local Probe for Magnetism and Spin Dynamics

Date:

5th October 2015 (Monday)

Time:

10:00 a.m.-11:00 a.m.

Venue:

FB-382

Abstract:

I will give a brief overview of Nuclear Magnetic Resonance (NMR) and the capability of this tool in uncovering the underlying mechanism for the emergent physical phenomena such as unconventional superconductivity and phase transitions on a microscopic scale in strongly correlated electron systems. I will also present our recent results on a new frustrated quantum magnet with exotic magnetic properties. Most of the physical phenomena in correlated electron materials often elude standard theoretical paradigms, even though the properties of the individual particles that constitute these materials are well established. In many cases, understanding the novel phases and establishing a suitable model in interacting quantum systems is still an unsettled issue, which signals the frontiers of our knowledge in this field. The development of modern material synthesis method, state art of the experimental techniques, and advances in theory have reinvigorated opportunities for investigating emergent properties of quantum materials. These materials might serve as model materials for hosting exotic excitations pertinent to novel states and to test theoretical conjectures [1,2,3]. Our recent comprehensive investigation demonstrates the role of persistent spin dynamics down to T→0 induced by frustration in stabilizing the exotic spin liquid state in a novel S = 1/2 frustrated quantum magnet [4]. References [1] P. Khuntia et al., Phys. Rev. Lett. 113, 216403 (2014). [2] P. Khuntia et al., Phys. Rev. B 86, 220401(R) (2012). [3] A. K. Nayak et al., Nature Materials, 14, 679 (2015). [4] P. Khuntia et al., (submitted to Phys. Rev. Lett.).


   

Speaker:

Jyotirmoy Bhattacharya

Affiliation:

Department of Mathematical Sciences, Durham University, UK.

Title:

Constraints on hydrodynamic transport phenomena from equilibrium partition functions.

Date:

23rd September 2015 (Wednesday)

Time:

4 PM

Venue:

FB-382

Abstract:

We will discuss the equilibrium thermal partition function for quantum field theories on arbitrary stationary background spacetime, in the long wavelength expansion. We shall first consider space-filling fluids and demonstrate that the equations of relativistic hydrodynamics are significantly constrained by the requirement of consistency with such a partition function. In this case, these constraints coincide precisely with the relations between transport coefficients that follow from the second law of thermodynamics. We will then use the power of this partition function formalism, to study and constrain the surface transport properties of fluids.


   

Speaker:

Jyotirmoy Bhattacharya

Affiliation:

Department of Mathematical Sciences, Durham University, UK.

Title:

Geometric aspects of quantum entanglement

Date:

22nd September 2015 (Tuesday)

Time:

4 PM

Venue:

FB-382

Abstract:

We shall begin with a brief introduction to the basic concepts behind the gauge-gravity duality. In this context, we will go on to describe how the notion of entanglement entropy in quantum field theory, acquires a geometrical interpretation. Using such geometric techniques, we will explore some interesting properties of entanglement entropy, which has close resemblance with thermodynamics laws. We will then speculate on how these properties may be helpful to recast gravitational dynamics as an effective dynamics of quantum entanglement, via the gague-gravity duality


   

Speaker:

Hilal Ahmed

Affiliation:

AMU, Aligarh

Title:

Synthesis and Characterization of Nanocrystalline Colossal
Magnetoresistive Manganites

Date:

13th February 2015 (Friday)

Time:

11 am

Venue:

FB-382

Abstract:

In this talk, I shall present results obtained on nanocrystalline Sr-doped LaMnO3. The parent material LaMnO3 is an antiferromagnetic insulator at room temperature. Strontium (Sr) doped LaMnO3 is an interesting manganite which shows ferromagnetism at room temperature with a rich phase diagram. These materials are well suited for spintronics and biomedical applications


   

Speaker:

Hilal Ahmed

Affiliation:

AMU, Aligarh

Title:

Synthesis and Characterization of Nanocrystalline Colossal
Magnetoresistive Manganites

Date:

13th February 2015 (Friday)

Time:

11 am

Venue:

FB-382

Abstract:

In this talk, I shall present results obtained on nanocrystalline Sr-doped LaMnO3. The parent material LaMnO3 is an antiferromagnetic insulator at room temperature. Strontium (Sr) doped LaMnO3 is an interesting manganite which shows ferromagnetism at room temperature with a rich phase diagram. These materials are well suited for spintronics and biomedical applications


   

Speaker:

Hilal Ahmed

Affiliation:

AMU, Aligarh

Title:

Synthesis and Characterization of Nanocrystalline Colossal
Magnetoresistive Manganites

Date:

13th February 2015 (Friday)

Time:

11 am

Venue:

FB-382

Abstract:

In this talk, I shall present results obtained on nanocrystalline Sr-doped LaMnO3. The parent material LaMnO3 is an antiferromagnetic insulator at room temperature. Strontium (Sr) doped LaMnO3 is an interesting manganite which shows ferromagnetism at room temperature with a rich phase diagram. These materials are well suited for spintronics and biomedical applications


   

Speaker:

Hilal Ahmed

Affiliation:

AMU, Aligarh

Title:

Synthesis and Characterization of Nanocrystalline Colossal
Magnetoresistive Manganites

Date:

13th February 2015 (Friday)

Time:

11 am

Venue:

FB-382

Abstract:

In this talk, I shall present results obtained on nanocrystalline Sr-doped LaMnO3. The parent material LaMnO3 is an antiferromagnetic insulator at room temperature. Strontium (Sr) doped LaMnO3 is an interesting manganite which shows ferromagnetism at room temperature with a rich phase diagram. These materials are well suited for spintronics and biomedical applications


   

Speaker:

Hilal Ahmed

Affiliation:

AMU, Aligarh

Title:

Synthesis and Characterization of Nanocrystalline Colossal
Magnetoresistive Manganites

Date:

13th February 2015 (Friday)

Time:

11 am

Venue:

FB-382

Abstract:

In this talk, I shall present results obtained on nanocrystalline Sr-doped LaMnO3. The parent material LaMnO3 is an antiferromagnetic insulator at room temperature. Strontium (Sr) doped LaMnO3 is an interesting manganite which shows ferromagnetism at room temperature with a rich phase diagram. These materials are well suited for spintronics and biomedical applications


   

Speaker:

Prof. A. P. Baburaj

Affiliation:

IIT Madras

Title:

The boundary layer velocity field in turbulent convection

Date:

25th April, 2015 (Saturday)

Time:

11 am

Venue:

Old core lab 103E

Abstract:

We measure the spatial velocity field in a horizontal plane within the velocity boundary layer over the horizontal hot plate in turbulent convection in water for 105 Ra 109 and Pr around 5. A new criterion is used to detect the coherent structures, namely line plumes, from this velocity field. The velocity field mostly shows four types of flow patterns, we present the PDF of velocities for each patterns to show their differences. The instantaneous velocity distributions match with that of laminar natural convection boundary layers, with the regions far away from plumes being affected by the external shear at the larger Ra. The mean velocity fields show no clear patterns and the fluctuating velocity fields show velocity field devoid of the mean shear, i.e. the pattern of flow driven by the plumes alone. The PDF of velocities of the plumes and the fluctuating components of the flow velocities coincide implying that plumes mostly contribute to the fluctuating velocity field. The joint PDF of horizontal and vertical instantaneous velocities show an 'arrow' type structure with the arms of the arrow head showing plume and boundary layers while the arrow shaft showing shear affected regions. The spectra of instantaneous velocities show a Bolgiano-Obukhov scaling at larger wave numbers while it shows a -1 scaling for lower wave numbers; we show that the -1 scaling is from regions affected by shear.


   

Speaker:

Dr. Srimanta Middey

Affiliation:

Department of Physics, University of Arkansas, USA

Title:

Heterointerface Engineering of Correlated Oxides

Date:

14th April 2015 (Tuesday)

Time:

4 PM

Venue:

FB-382

Abstract:

Periodic geometrical arrangement of the constituent atoms in a crystalline solid is the backbone of electronic and magnetic properties. The alternation of this atomic arrangement, by creating interface between two chemically, electronically and structurally dissimilar materials can be expected to result a set of many-body states, which are unattainable in the constituent bulk materials. As the strong intercoupling among spin, charge, orbital, lattice degrees of freedom in correlated oxides promote various fascinating collective phenomena (e.g. superconductivity, magnetism, ferrolectricity ...), the additional broken symmetries and frustrated couplings across interface may give rise to a new horizon to novel electronic, magnetic and topological states. However, microscopic understanding of such interfacial properties is a grand challenge and it requires various advanced techniques. In this talk, I will illustrate the success in creating `new’ electronic states by growing transition metal oxide superlattices with unit cell precision. The implementation of synchrotron diffraction, x-ray absorption spectroscopy, resonant x-ray scattering experiments to elucidate the response of the underlying structures, spins, orbitals and charges due to this heterostructuring will be also discussed. Additionally, I will present the prospect of such engineered heterointerfaces for energy harvesting and application as next generation materials for Mott electronics.


   

Speaker:

Auditya Sharma

Affiliation:

Tel Aviv University, Israel

Title:

Landauer current and mutual information

Date:

14th April, 2015

Time:

2.30 PM

Venue:

FB-382

Abstract:

We study quantum evolution of the density matrix of a quantum dot con- nected to left and right leads initially maintained at chemical potentials µL and µR respectively and temperature T, within the non-interacting resonant-level model. The full nonequilirbium mixed state density matrix of the whole system is written down exactly, and the mutual information of the dot with respect to the leads is computed. A strong and direct correlation is found between the Landauer current, and the mutual information at all times, the steady-state values in particular displaying a quadratic relationship at high temperatures. We argue that this relationship could potentially be exploited experimentally to ‘measure’ mutual information. I will try to give an elementary introduction and build up the technical details gradually.References: [1] Auditya Sharma and Eran Rabani. Phys.Rev.B 91, 085121 (2015).


   

Speaker:

Gagan Kumar

Affiliation:

IIT Guwahati

Title:

Terahertz Plasmonic Waveguides

Date:

9-April-2015 (Thursday)

Time:

3 PM

Venue:

FB-382

Abstract:

Plasmonic metamaterials have the ability to facilitate the next generation miniaturized high speed communication devices and networks. In my talk, I will discuss about the design, fabrication and characterization of the terahertz guided wave devices on the planar surfaces using plasmonic metamaterials. Thin metal films when periodically corrugated with subwavelength scale structures forms a plasmonic waveguide, which can result in the propagation of terahertz modes confined in both the transverse directions. The degree of confinement and frequency of the resonant modes can be controlled with the geometrical parameters of the structures. In my talk, I will also discuss about the possibly of replacing metals substrates with semiconductors for such waveguide which can be advantageous in making active components.


   

Speaker:

Dr. R. Prabhu

Affiliation:

HRI, Allahabad

Title:

Multipartite quantum correlations in many-body systems.

Date:

8th April, 2015 (Wednesday)

Time:

4 PM

Venue:

FB-382

Abstract:

The cross-braiding between quantum information and condensed matter physics has recently stimulated excitation among researchers. Many-body systems are potential physical substrates to realize several quantum information protocols. The tools developed in quantum information have been put to use in analyzing collective phenomena in many-body systems. Many-body systems have been studied by observing, for example, their response to external perturbations, various order parameters, and excitation spectra. In this talk, I will characterize the behavior of several quantum correlation measures, including bipartite and multipartite ones, in spin models like Heisenberg spin system, XY-spin chain, etc. Also, I deal with the characterization of multipartite quantum correlation in spin models which can be both clean and disordered ones.


   

Speaker:

Dr. Arijit Kundu

Affiliation:

IU Bloomington, IN, US

Title:

Topology and Transport in Periodically Driven Systems

Date:

31st March, 2015 (Tuesday)

Time:

4 PM

Venue:

FB-382

Abstract:

One way to introduce topological phases in certain systems is periodic driving. For example, an 1D p-wave superconductor, driven periodically, can go through a Floquet transition to become topologically non-trivial. Such Floquet topological superconductor can host exotic steady states, which are called Floquet Majorana fermions. Whereas, graphene, under the application of circularly polarized laser is an example of Floquet topological insulator. Such topological insulators, like the quantum-hall systems, have non-trivial topology and chiral edge states. Such systems present potential applications to various fields from quantum computation to valleytronics. In this talk I'll present our recent works on topological classification and some novel transport characteristics of such driven systems.


   

Speaker:

Dr. Veeresh Singh

Affiliation:

University of KwaZulu-Natal Durban, South Africa

Title:

Unveiling the population of distant radio galaxies and their environments

Date:

31st March, 2015 (Tuesday)

Time:

12 noon

Venue:

FB-382

Abstract:

Radio galaxies exhibit jet-lobe radio structures emanating from active nucleus and are found to be hosted in massive elliptical galaxies. Radio galaxies particularly at higher redshifts and in obscured environments can be used as beacon to identify active galaxies and understand their evolution. It has been shown that Ultra Steep Spectrum (USS) radio sources are one of the efficient tracers of powerful High-z Radio Galaxies (HzRGs). We study properties of a USS sample derived from deep 325 MHz and 1.4 GHz observations and find a substantial population of unexplored weaker radio galaxies potentially hosted in obscured environments along with the population powerful HzRGs. Furthermore, in general, powerful HzRGs tend to reside in (proto)cluster environments.


   

Speaker:

Dr. Debakanta Samal

Affiliation:

Max-Planck Institute, Munich, Germany

Title:

Tailoring the electronic properties of cuprate layers on unit cell level: A boost towards designing artificial high Tc cuprates.

Date:

26th February, 2015 (Thursday)

Time:

4.30 PM

Venue:

FB-382


   

Speaker:

Dr. Dinesh Narayana Naik

Affiliation:

Department of Physics, Mehsana Urban Institute of Sciences, Ganpat University

Title:

Correlation holography: A marriage of holography with statistical optics

Date:

25th February, 2015 (Wednesday)

Time:

4 PM

Venue:

FB-382

Abstract:

With unconventional holographic techniques incoherent holography, coherence holography and photon correlation holography, it is possible to record and reconstruct 3-D objects as the second or fourth order correlation function of the optical fields. Unlike conventional holography, these techniques require only incoherent light for the illumination. The reconstructed object manifests itself in the spatial coherence function of the optical field. As a consequence, we can extend the holographic imaging to phenomena such as fluorescence with possible biomedical applications. Moreover, optical fields with a desired spatial coherence function can be synthesized using the technique of coherence holography with possible applications to microscopy and lithography.


   

Speaker:

Dr. Vishwanath Shukla

Affiliation:

IISc, Bangalore

Title:

Particles And Fields In Superfluids: Insights From The Two-Dimensional Gross-Pitaevskii Equation.

Date:

23th February 2015 (Monday)

Time:

4 PM

Venue:

FB-382

Abstract:

We study the dynamics of active particles in two-dimensional superfluids at temperature T = 0, for a variety of initial configurations, by carrying out extensive direct-numerical-simulations of the two-dimensional, Galerkin-truncated Gross-Pitaevskii equation. Our study elucidates the interplay of particles and fields, in both simple and turbulent flows. We show that particle collisions can be inelastic, if the repulsive interactions between particles is weak, and elastic otherwise. We show that assemblies of many particles and vortices yield turbulent spatiotemporal evolutions.


   

Speaker:

Hilal Ahmed

Affiliation:

AMU, Aligarh

Title:

Synthesis and Characterization of Nanocrystalline Colossal
Magnetoresistive Manganites

Date:

13th February 2015 (Friday)

Time:

11 am

Venue:

FB-382

Abstract:

In this talk, I shall present results obtained on nanocrystalline Sr-doped LaMnO3. The parent material LaMnO3 is an antiferromagnetic insulator at room temperature. Strontium (Sr) doped LaMnO3 is an interesting manganite which shows ferromagnetism at room temperature with a rich phase diagram. These materials are well suited for spintronics and biomedical applications


 

Speaker:

Dr. Debi Prasad Datta

Affiliation:

Institute of Physics (IoP), Bhubaneshwar

Title:

Ion beam induced synthesis and modifications of nano structures:
Fundamentals and some applications.

Date:

14th January, 2015 (Wednesday)

Time:

12 pm

Venue:

FB-382

Abstract:

Ion bombardment of solids is an efficient route towards processing of nano-scale surface patterns as well as synthesis and modification of nanostructures. Ion-beam-patterned surfaces are receiving increasing interest due to their promising applications, e.g., as templates for growing thin films with tailored properties. In this talk, I shall present our experimental investigations on the evolution of surfaces under off-normally incident medium energy ion bombardment. In fact, I shall show that ripple pattern evolution on Si[1], Ge[2], or SiO2 can be understood in a common theoretical framework, viz. as a result of ion erosion and ion induced mass redistribution. Irradiation-induced transition of such sinusoidal ripple patterns to a saw-toothed one will be demonstrated, which will be correlated to slope-dependent non-linear effect and shadowing of the incident ion beam. On the other hand, similar off-normal ion bombardment will be shown to result in no surface patterning but development of a porous structure containing nanofibers in case of GaSb and InSb [3], owing to growth of voids during bombardment. Some properties of such ion-induced structures, like photoluminescence, antireflection and hydrophobicity, will be discussed. In the last part of the talk, I shall describe studies on synthesis and modification of embedded Au nanoparticles in SiO2 by MeV Au2+-ion bombardment [4].
1. D. P. Datta et al., Phys. ReV. B 69, 235313 (2004); Phys. Rev. B 71, 235308 (2005); Phys. Rev. B 76, 075323 (2007), S. K. Garg and D. P. Datta
et al., Appl. Surf. Sci. 310, 147 (2014); Appl. Surf. Sci. 317, 476 (2014).
2. D. P. Datta et al., (to be communicated to Phys. Rev. B).
3. D. P. Datta et al., J. Appl. Phys. 115, 123515 (2014); Applied Surface Science 310, 189 (2014); J. Appl. Phys, 116, 033514 (2014); J. Appl. Phys. 116, 143502 (2014).
4. D. P Datta et al., Appl. Surf. Sci. 310, 164 (2014).


 

Speaker:

Faraz Ahmed Inam

Affiliation:

Dept. of Physics, Aligarh Muslim Universiuty

Title:

Fundamental characterisation of nanodiamond nitrogen-vacancy (NV) centres spontaneous emission as a single photon source.

Date:

06 January 2015 (Tuesday)

Time:

3 pm

Venue:

FB - 382

Abstract:

With its inbuilt, unique spin and optical properties, negatively charged nitrogen-vacancy (NV) centres in diamond have attracted wide interest in interdisciplinary research fields, ranging from quantum technologies, high-resolution magnetometry to biomedical imaging and tracking. Most of the highly sensitive applications of diamond-NV centers in the above fields rely on bright, controllable and photo-stable NV luminescence from very small diamond nanocrystals. Nanodiamond NV centre has been widely studied in the past decade and significant enhancements in its emission rate and capture factors were achieved. Nevertheless a complete picture of its spontaneous emission under the influence of the local electromagnetic nano-environment was non-existent at the beginning of my research study. In my research, I sought to improve the understanding of NV emission by systematically isolating the various individual mechanisms influencing its emission.

In this talk, I will shows how the systematic approach of our study of nano diamond NV emission under a range of conditions and environments elped us to develop and contribute towards the evolved understanding of
its spontaneous emission.


 

Speaker:

Dr. Swapnil Patil

Affiliation:

Tata Institute of Fundamental Research (TIFR)

Title:

Photoemission insight into exotic low temperature physics of
rare-earth intermetallics: heavy-fermion behaviour, mixed valency,
Kondo physics etc.

Date:

6th January, 2015 (Tuesday)

Time:

12 pm

Venue:

FB - 382

Abstract:

In this talk, I shall present the results of photoemission studies of remarkable Ce- and Yb- based materials, exhibiting unique properties like Kondo physics, heavy-fermion behaviour, and mixed valency. One of the important problems in correlated electron systems concerns the observation of "large-small" Fermi surface transition in Kondo systems with temperature. It is believed that the Fermi surface of a Kondo system expands at lower temperatures due to the formation of many-body Kondo singlet states. Our photoemission results however demonstrate temperature invariant Fermi surface in a prototypical Kondo system, YbRh2Si2. Additionally our results on Ce-Kondo systems demonstrate electronic spectral evolution which deviates from the predictions of Anderson model, a theoretical model normally used to interpret photoemission spectra from Kondo systems. Potential candidates to explain these discrepancies will be briefly discussed. Finally Fermi surface studies on YbCo2Si2, a stable valent Kondo lattice, will be discussed which serves as a reference compound for YbRh2Si2, which happens to be close to quantum criticality.


Speaker:

Dr. Sunil Kumar

Affiliation:

Weizmann Institute of Science, Israel

Title:

Contolled multiphoton micro-spectroscopy for high resolution imaging applications.

Date:

22nd October, 2014 (Wednesday)

Time:

11 am

Venue:

FB-382


 

Speaker:

Dr. Sita Sunder

Affiliation:

Postdoc in Physics, IIT Kanpur

Title:

Flow shear driven instability in EMHD

Date:

16 September 2014

Time:

4 pm

Venue:

Old corelab 103E Meeting Room


 

Speaker:

Sriram Guddala

Affiliation:

Metamaterials & Plasmonics Lab, Department of Physics, IIT Kanpur

Title:

Metal-Dielectric Periodic Photonic Structures

Date:

27 August 2014 (Wednesday)

Time:

3 pm

Venue:

FB - 382

Abstract:

The optical field confinement in periodic metal-dielectric photonic structures has been of great interest to achieve intense localized electric field strengths due to unified properties driven from plasmonic properties of metallic nanostructures and photonic band gap properties of periodic dielectric structures [1]. Here, the metal-dielectric photonic crystals (MDPCs) and some preliminary results on metamaterial perfect optical absorbers be discussed. In the context of MDPCs, it will be shown that the confined optical fields resulted from redistributed photon density of states and their influence on enhancement of Raman scattering in metal nanoparticles impinged 3D (inverse opal structures) and 1D (multilayered microcavity) photonic crystals [2-3] . The intense optical fields are obtained on excitation of band edge (3D opals) and defect state (1D microcavity) photonic modes of photonic band gap structures and their coupling to the surface plasmon resonance properties of impinged metal nanoparticles. These intense optical fields were further probed by performing spectral and angle resolved surface enhanced Raman scattering (SERS) studies, and the enhancement of Raman scattering is understood through a novel photon-plasmon-phonon interaction mechanism. Our studies show a novel aspect of PBG influence to accomplish a highly reliable periodic metal-dielectric SERS substrate for sensing and photonic applications. At the end it will be discussed some of the recent studies on design, fabrication and characterization of novel architectures of multilayer metal-dielectric perfect optical absorbers for visible and NIR wavelengths.
References:

[1] S. Guddala, K. Shadak Alee, and D. Narayana Rao, "Fabrication of multifunctional SnO2 and SiO2-SnO2 inverse opal structures with prominent photonic band gap properties," Opt. Mater. Express 3, 407-417 (2013).
[2] S. Guddala, V. K. Dwivedi, G. Vijaya Prakash and D. Narayana Rao, "Raman scattering enhancement in photon-plasmon resonance mediated metal-dielectric microcavity," Journal of Applied Physics, 114, 224309 (2013).
[3] S. Guddala, K. S. Alee, A. Chiappini, M. Ferrari, and D. Narayana Rao, "Experimental investigation of photonic band gap influence on enhancement of Raman-scattering", Journal of Applied Physics, 112, 084303 (2012).


 

Speaker:

Dr. Ipsita Mandal

Affiliation:

Perimeter, Waterloo

Title:

Low Energy Physics of a Non-Fermi Liquid System

Date:

20 August 2014

Time:

3 pm

Venue:

FB - 382

Abstract:

We devise a renormalization group analysis for quantum field theories with Fermi surface to study scaling behaviour of non-Fermi liquid states in a controlled approximation. The non-Fermi liquid fixed points are identified from a Fermi surface in (m+1) spatial dimensions, while the co-dimension of Fermi surface is also extended to a generic value. We also study superconducting instability in such systems as a function of dimension and co-dimension of the Fermi surface. The key point in this whole analysis is that unlike in relativistic QFT, the Fermi momentum kF enters as a dimensionful parameter, thus modifying the naive scaling arguments. The effective coupling constants are found to be combinations of the original coupling constants and kF.

Speaker:

Prof. Sayan Kar

Affiliation:

IIT Kharagpu

Title:

Eddington-inspired Born-Infeld gravity

Date:

27th March 2014, Thursday

Time:

4 pm

Venue:

FB - 382


 

Speaker:

Dr. Sinu Mathew

Affiliation:

NUSNNI-NanoCore and Dept. of Electrical and Computer Engineering, National University of Singapore

Title:

The Effects of MeV Proton Irradiation on Interface Two-Dimensional Electron Gas (LaAlO3/SrTiO3) and Layered Solids (MoS2,graphene)

Date:

3rd March 2014, Monday

Time:

12:00 pm - 1:00 pm.

Venue:

FB - 382

Abstract:

The two-dimensional electron gas (2DEG) formed at the interface between two band insulators LaAlO3 (LAO) and SrTiO3 (STO) is one of the most fascinating systems in the field of oxide research. Tailoring of the conductivity of this interface 2DEG is a challenge for the practical
applications of this system. MeV Proton irradiation on LAO/STO system is found to manipulate interfacial conductivity by carrier localization and eventually producing an insulating ground state by tailoring the defect structure of the substrate STO. The results of electrical and magneto-transport, Raman spectroscopy and spectroscopic ellipsometry will be discussed[1]. The second part of the talk will be on the effects of MeV Proton irradiation on Molybdenum disulphide and graphene. MoS2 a diamagnetic layered solid, is found to show ferrimagnetic ordering at room temperature when exposed to 2 MeV proton beam[2]. A disorder mode corresponding to a zone-edge phonon and a valency of Mo higher than +4 have been detected in the irradiated samples. The stability of supported and suspended graphene under MeV Proton irradiation will also be discussed[3]. References

  1. S. Mathew, A. Annadi, T.K. Chan, Teguh Citra Asmara, D. Zhan, Ariando, A. Rusydi, Z.X Shen, M.B.H. Breese and T. Venkatesan. ACS Nano 7 (2013) 10572

  2. S. Mathew, K. Gopinadhan , T.K. Chan, X.J. Yu, D. Zhan, L. Cao, A. Rusydi, M.B.H. Breese,

  3. S. Mathew, T.K. Chan, D. Zhan, K. Gopinadhan, A.R. Barman, M.B.H. Breese, S. Dhar, Z.X. Shen, T.Venkatesan and John TL Thong. Carbon 49 (2011) 1720; J. Appl. Phys. 110 (2011) 84309


 

Speaker:

P. Santhana Raman (Post-doctoral fellow at Institute of Physics, Bhubaneswar)

Affiliation:

Centre for Ion Beam Applications, Department of Physics, National University of Singapore, Singapore

Title:

Research and Development with Energetic Broad- and Nano- Ion Beams:From Ion Beam Analysis to Novel Materials Modification and Proton Beam Writing Systems

Date:

24th February, 2014 (Monday)

Time:

3:30 pm - 4:30 pm.

Venue:

FB - 382

Abstract:

The process that can be accomplished using energetic ion beam technique broadens itself with no limit. Starting from routine materials analysis (via various Ion beam analysis technique), the advent of ion beam extends to carve and alter structures at nano scale, with nano-sized ion beam, to form novel materials. The cause and the effect of these energetic ion beams on both materials and soft-tissues are of paramount importance in understanding it in terms of both fundamental and application point of view. This talk will cover the Ion beam analysis techniques that were crucial in novel materials synthesis (especially with embedded InN and ZnO nanoclustres in silica matrix). The systematic approach, using energetic ion beams, in producing surface patterns will be discussed in the light of basic physics and its applications. Later in the talk I will introduce and explain about the next generation lithographic technique, namely Proton Beam Writing and its capability to produce high aspect ratio nanostructures. The developmental activities involved in making of high brightness ion source, to be used in next generation compact proton beam lithography, with a promise to deliver sub-10 nm beam spot size, will also be discussed.


 

Speaker:

Dr. Haraprasanna Lenka (Post-doctoral fellow at Institute of Physics, Bhubaneswar)

Title:

Microscopic characterization of GaN heterostructures using RBS/C and TEM: A comparative study.

Date:

January 16th, 2014 (Thursday)

Time:

4:00 pm - 5:00 pm.

Venue:

FB - 382

Abstract:

Recently, the success of the growth of high quality c-GaN layers on Si substrate has attracted considerable academic and commercial interest, because it can facilitate the integration of microelectronics and optoelectronics. But the large lattice and thermal mismatch between GaN and Si introduces a lot of dislocations which pose a major obstacle in the production of defect-free layers, much needed for device applications. Hence, material processing requires intermediate monitoring to quantitatively track the amount of defects formed during growth. Apart from measuring the critical characteristics like the dislocation density,
a good estimation of strain and composition is also important for device optimization. To meet this challenge, ion channeling is a very attractive and a powerful technique because of its unique mass sensitivity to the type of defects separately (such as point defects, dislocations, stacking faults or defect clusters). Results of RBS/C will be presented as a fast and non-destructive technique to analyze the defect density and the elastic strain, two parameters which can potentially affect the device performance in comparison with TEM results.


 

Speaker:

Debanjan Chowdhury (Harvard University)

Title:

Unconventional phases of quantum matter

Date:

January 15th, 2014 (Wednesday)

Time:

11:00 am - 12:00 pm.

Venue:

FB - 382

Abstract:

Theorists have been studying unconventional states of quantum matter over the past few years and starting recently, experiments on such states have finally appeared, generating much excitement. I will describe experimental observations on high temperature superconductors and magnetic insulators and their influence on our theoretical understanding. In the first part of the talk, I will introduce the theory of quantum criticality in metals and apply it to the phase diagrams of the high temperature superconductors. I'll review some of the experiments on the iron pnictides, which point toward the possible existence of a quantum critical point underneath the superconducting dome and try to offer a partial explanation for some of the mysterious observations[1]. In the second part of the talk, I'll review some recent experiments on a kagome lattice anti-ferromagnet and argue that many of the observed features can be explained by the presence of fractionalized excitations in a quantum spin liquid[2].
[1] D. Chowdhury, B. Swingle, E. Berg and S. Sachdev, Phys. Rev. Lett. 111,
157004 (2013).
[2] M. Punk, D. Chowdhury and S. Sachdev, Nature Phys. (to appear), 2014;
arXiv:1308.2222.


 

Speaker:

Dr. Sanjay Kumar Mandal (NIT Agartala)

Title:

Multiferroic Composites for Magnetic Field Sensors.

Date:

December 9th, 2013

Time:

11:30 am - 12:30 pm.

Venue:

FB - 382

Abstract:

Multiferroics with two or more ferroic (ferroelectric, ferro/ferri/anti-ferromagnetic, ferroelastic) orderings have attracted considerable attention in recent years. Single-phase multiferroics are rare and their magnetoelectric (ME) responses are either weak or occur at temperatures too low for practical applications. Ferromagnetic-piezoelectric composites, however, show strong ME coupling at ambient temperatures. The ME effect is a property mediated by elastic
deformation. The composites show a rich variety of phenomena including giant low-frequency ME interactions. This presentation will focus on recent developments in the physics and applications of composite multiferroics. The discussion will include our work on functionally graded composites for use as ultra sensitive magnetic field sensors.


 

Speaker:

Dr. Aditya Kelkar (TIFR, Mumbai)

Title:

Ion collisions with molecules and Clusters

Date:

January 8th, 2014 (Wednesday)

Time:

4:00 pm - 5:00 pm.

Venue:

FB - 382

Abstract:

The description of the temporal and spatial evolution of systems of mutually interacting particles is of fundamental importance in atomic collision physics. Theoretically the difficulty of this task lies in the fact that the Schrödinger equation is not analytically solvable for more than two particle systems even when the underlying forces are precisely known. On the other hand collisions with photons and charged particles (electrons and heavy ions) have proved to be excellent tools to investigate the structural and dynamical properties of physical systems like atoms, molecules, clusters and solid surfaces etc. The dynamics can be studied in a wide range of Coulomb interaction strength and time scales by suitable choice of heavy ion beams, offering the opportunity to study a multitude of processes such as ionization and capture, radiative and non-radiative relaxation etc to coherence effects and collective behaviour in many body systems as well as bond formation and rearrangement in chemical reactions. In this talk I shall discuss the interaction of heavy ions with many body systems taking two examples from my research work. In the first part, I will describe collisions of highly charged heavy ions with fullerene C60 in the intermediate velocity (vp ~ 10 a.u.) range, focusing on the excitation of a collective surface plasmon mode known as Giant dipole plasmon resonance or GDPR. In this velocity range the dwell time of the projectile ion is ~10-17 seconds and the interaction can be treated in the perturbative regime. However, in collisions at very low energy (vp ~ 0.01 a.u.) the interacting particles have sufficient time for electronic rearrangement and bond formation leading to chemical reactions. In particular I will discuss the dynamics of a bimolecular nucleophilic substitution reaction between F - (anion) and CH3Cl in gas phase using velocity map imaging (VMI) technique.


 

Speaker:

Dr. Arijit Saha (University of Basel, Switzerland)

Title:

Novel Transport phenomena in hybrid junctions of Nanowires

Date:

January 7th, 2014 (Friday)

Time:

2:45 pm - 3:45 pm.

Venue:

FB - 382

Abstract:

In the first part of the talk I shall give a brief introduction to my field of research called "Mesoscale and Nanoscale Physics" highlighting the subfield of low dimensional systems with examples and experiments. In the next part, I shall talk about transport properties of hybrid superconducting junctions of one dimensional n a no wi r es (NW). In particular, I shall demonstrate possible scenarios for production of pure spin current through such junctions. I shall also show that (a) effects due to inclusion of electron-electron interaction induced back-scattering in the wire, and (b) competition between the charge transport via the electron and hole channels across the junction give rise to a non monotonic behavior of the sub gap conductance as a function of temperature. ln the last part of the talk I shall introduce NW in the presence of Rashba spin orbit interaction, uniform magnetic field, and spatially modulated magnetic field. Such fully gapped system can support fractional fermion (FF) bound states at the two ends of the NW. I shall discuss the transport and noise signatures of such FF bound states which has never been investigated so far in literature.


 

Speaker:

Dr. Jaivardhan Sinha (National Institute for Materials Science (NIMS), Tsukuba, Japan)

Title:

Perpendicular magnetic anisotropy and current induced effective field in Ta(N)|CoFeB|MgO

Date:

December 6th, 2013

Time:

12:00 pm - 01:00 pm.

Venue:

FB - 382

Abstract:

Perpendicular magnetic anisotropy (PMA) originating from the interface in Heavy metal(Pt, Ta)|Ferromagnet(Co, CoFeB)|Oxide structure (Al2O3, MgO) is of great interest because of its potential application in spintronics based devices. The recent finding of spin-orbit torque (spin Hall spin torque) in these heterostructures [1,2] has increased its significance manifold as it allows one to manipulate magnetization direction using in-plane current. Solid understanding the role of Heavymetal|Ferromagnet interface and Ferromagnet|Oxide interface is essential for utilizing them in application. In this talk I shall discuss the Ta|CoFeB interface properties in Ta(N)|CoFeB|MgO and the current induced effective field likely generated due to spin Hall effect from Ta. In general, Ta is known for creating a magnetic dead layer when placed next to a magnetic layer. As the CoFeB layer thickness is of the order of 1 nm to obtain PMA, thus it is desirable to have negligible magnetic dead layer from the point of view of thermal stability. The effect of Nitrogen doping in Ta underlayer on interface anisotropy, magnetic dead layer thickness and current induced effective field will be also discussed [3].

References:
[1] Junyeon Kim, Jaivardhan Sinha, Masamitsu Hayashi, M. Yamanauchi, S. Fukami, T. Suzuki, S. Mitani and Hideo Ohno, Nature. Materials. 12, 240 (2013).[2] L. Liu, C. F. Pai, Y. Li, H. W. Tseng, D. C Ralph, and R. A. Buhrman, Science 336, 555 (2012).
[3] Jaivardhan Sinha et al, Appl. Phys. Lett. 102, 242505 (2013).


 

Speaker:

Dr. Shibabrata Nandi (Jülich Centre for Neutron Science & Peter Grünberg Institute)

Title:

Structure, magnetism and superconductivity in Fe-based
superconductors

Date:

November 27th, 2013

Time:

11:30 am - 12:30 pm.

Venue:

L8 (LHC)

Abstract:

In iron-based high-temperature superconductors, magnetic fluctuations and magneto-elastic effects are believed to be important for the superconducting electron pairing mechanism. To gain insight into the interplay between the different ordering phenomena and the underlying couplings we studied the magnetic order and lattice distortion on AFe2As2 (A = Ca, Sr, Ba, Eu) single crystals by neutron and x-ray diffraction. High-resolution x-ray diffraction and neutron scattering measurements reveal an unusually strong response of the lattice and ordered magnetic moment to superconductivity in Co-doped BaFe2As2 . We propose that the coupling between lattice and superconductivity is indirect and arises due to the magnetoelastic coupling, in the form of emergent nematic order, and the strong competition between the magnetism and superconductivity. For the P-doped EuFe2As2 , coexistence between the ferromagnetism and superconductivity was observed and explained in terms of formation of a spontaneous vortex state.


 

Speaker:

Dr. Ajay Soni (School of Basic Sciences, IIT Mandi, Himachal Pradesh)

Title:

Nanocomposites of Layered Chalogenides for
Thermoelectric Applications

Date:

November 26th, 2013

Time:

12:15 Pm - 1:15 pm.

Venue:

L9 (LHC)

Abstract:

Research in the field of thermoelectricity (TE) is full of outstanding ideas, the materials having properties of an electron-crystal-phonon-glass, such as rattling semiconductors, alloys, heterostructures, and bulk-nanocomposites have shown to be efficient TE materials. In this context, the nanocomposites of layered chalcogenides (Te and Se) and pnictogen (Bi and Sb) materials have been preferably studied for their high-performance TE properties arising due to layered structure and narrow band gap.1 The efficiency of the TE material is quantified by a dimensionless thermoelectric figure of merit, $ZT = S^2\sigmaT/\kappa$, where S is the Seebeck coefficient, $\sigma$ is the electrical conductivity, $\kappa$ is the thermal conductivity and T absolute temperature. Thus the interplay of the three physical parameters makes the problem very complex for TE materials. The research talk will focus on a novel class of solution grown Bi2Te3-xSex nanoplatelet composites (NPCs) having an enhanced thermoelectric properties2 , and the effects of the thermodynamic environment during spark plasma sintering.3For the case of NPCs, the grain boundaries and interfaces are playing important role such that the charge carriers and phonons couple in a unique fashion. The subtle understanding of the interface crystallization, grain growth and filtering of electron and phonons will be discussed. A brief notion on the family of layered materials and their technological aspects will also be emphasized.

References:
1. Dresselhaus, M. S., Adv. Mater. 2007, 19, 1043-1053.
2. Soni, A.; Yanyuan, Z.; Ligen, Y.; Aik, M. K. K.; Dresselhaus, M. S.; Xiong, Q., Nano Letters 2012, 12 (3), 1203.
3. Soni, A.; Yiqiang, S.; Ming, Y.; Yanyuan, Z.; Ligen, Y.; Xiao, H.; Zhili, D.; Aik, M. K. K.; Dresselhaus, M. S.; Xiong, Q., Nano Letters 2012, 12 (8) 4305


 

Speaker:

Dr. A K Sinha (Centre-Director, UGC DAE Consortium for Scientific Research, Kolkata)

Title:

Manipulating Ions for Science & Technology

Date:

November 25th, 2013

Time:

04:00 pm - 05:00 pm.

Venue:

FB 382

Abstract:

We manipulate photons to form a beam of laser which finds numerous
applications. In a somewhat similar way, we manipulate fast moving
ions to use them in a very wide spectrum of scientific studies.
Many technologies emerge out of these.

I will try to cover some of the examples from my work involving such
ion manipulations. Then i will make an attempt to dwell on such ion
manipulations and their use in the Ion Beam Complex at IITK.


 

Speaker:

Dr. Bholanath Pahari (IISc Bangalore)

Title:

Probing Microscopic Information of Complex Materials by
Nuclear Magnetic Resonance Techniques.

Date:

November 21th, 2013

Time:

11:00 am - 12:00 noon.

Venue:

FB 382

Abstract:

Solid-state nuclear magnetic resonance (NMR) spectroscopy is a powerful physical method widely applied in modern fundamental and applied science. The two most important modes of solid state NMR for obtaining local physical and chemical information are wide-line static NMR and high-resolution magic angle spinning (MAS) NMR. Applications of both NMR modes and their advantages for the investigation of different categories of complex material will be discussed. Present seminar targets following three different topics.

  1. 51V NMR studies to understand the nature of ground state and low-lying excitations in the integer spin chain (also known as Haldane chain) compound SrNi2V2O8.

  2. 75As NMR for the investigation of electronic and lattice properties of recently discovered iron arsenide high-temperature superconductor CeFeAsO1−xFx (TC ∼ 40 K).

  3. Multinuclear MAS NMR studies to understand the structure - property relationships in oxide-ion conducting materials of P − doped La2Mo2O9 .


 

Speaker:

Dr. Shirish Chodankar (SLS, Paul Scherrer Institut, Switzerland)

Title:

Hydration forces and ion-ion correlation in confined
fluids revealed by X-ray Reflectivity

Date:

November 18th, 2013

Time:

11:30 am - 12:30 pm.

Venue:

FB 382

Abstract:

When a liquid is confined within a nanometer-sized gap, the combination of interfacial effects and size often confer to the system properties much different from those observed in bulk fluids [1]. In particular, understanding the structure of electrolytes confined between two aluminium-phyllosilicates walls could be enlightening in a number of fields, ranging from biology to nuclear waste management, as well as clarify some fundamental issues regarding alkali hydration energies and their influence on the surrounding hydrogen bond network. We have adapted a surface force apparatus (SFA) [2] to be used as confinement device for two sets of X-ray reflectivity (XRR) experiments conducted at the cSAXS (XSA12) beamline of the Swiss Light Source at PSI. In the first set of experiments, we determined by use of XRR the distance between the surfaces and the electron density profile of the naturally present water across the hydrophilic gap at nominal zero humidity [3]. In the second set, the natural layer of K+ ions present on cleaved mica surfaces was substituted with monovalent Rb+ or divalent Sr2+ ions. In the third set droplets of RbCl, CsCl and BaCl2 solutions at different concentrations were nano-confined. We have quantitatively determined the minimum gap distance between the mica surfaces at ~ 105 Pa applied pressure under the influence of different surface ions and electrolytes. In all cases we have observed layered electron density profiles within the gap, with the layering generally being stronger for more strongly correlated systems. A comparison between confined chloride solutions with different monovalent and divalent cations (Cs+ , Rb+ and Ba2+) reveals cation specific effects which can be related to concentration, ion size and hydration behavior. For example, we observe characteristic differences between the relative proportions of hydrated inner- and outer-sphere species and in the coverages of the inner membrane surfaces by directly adsorbed ions. Moreover, ordering in strongly correlated BaCl2 is interpreted as alternate cation-anion layering. Structure models for the measured density profiles will be presented and discussed.
References:
1. Israelachvili, J.N., Intermolecular and surface forces: revised third edition. 2011: Academic press.
2. Perret, E., et al., Molecular liquid under nanometre confinement: density profiles underlying oscillatory forces. Journal of Physics: Condensed Matter, 2010. 22(23): p. 235102.
3. Chodankar, S., et al., Density profile of water in nanoslit. EPL (Europhysics Letters), 2012. 99(2): p. 26001.


 

Speaker:

Dr. Saurabh Mani Tripathi
Photonics Research Centre, Department of Computer Science and
Engineering, University of Quebec at Outaouais, Canada.

Title:

Long period grating and multimodal interference effect
based fiber-optic sensors

Date:

October 21st, 2013

Time:

3 pm - 4 pm

Venue:

FB 382

Abstract:

In this seminar I will present my resent research activities on the development of fiber-optic sensors based on (I) long-period gratings and (ii) single-multi-single (SMS) fiber optic structures. The first part
of my talk will deal with the development of bio-sensors for rapid, reliable and quantitative detection of pathogenic E. coli bacteria in water. In the second part I will discuss the role of a critical wavelength
in the performance of fiber optic devices based on modal interference. Application of modal-interference effects in bio-therapy will also be discussed.

Quic Talk:

Speaker:

A. Kani (Dept. Of Physics, IITK)

Title:

Harnessing quantum interference in atomic systems

Date:

October 7th, 2013

Time:

4 pm - 5 pm

Venue:

FB 382

Abstract:

Quantum interference between the excitation pathways modifies the optical response of the atomic system and leads to Coherent Population Trapping (CPT) and/or Electromagnetic Induced Transparency (EIT), or Electromagnetic
Induced Absorption (EIA), or Amplification without Inversion (AWI), or Enhanced Refractive Index with vanishing absorption. We will present a simple four-level atomic system interacting with a bi-chromatic light field
(double V-system) and discuss all these quantum interference effects and discuss the way to control over these effects.

Seminar:

Speaker:

Dr. Sayantani Bhattacharyya (Ramakrishna Mission Vivekanand University)

Title:

Detecting biomass burning emission over South East Asia from space.

Date:

September 16th, 2013

Time:

11 am - 12 am

Venue:

FB 382

Abstract:

Fluid dynamics is controlled by Navier Stokes equation. On the other hand Einstein equations control the dynamics of classical gravity. Both are complicated non linear partial differential equations with rich structure
in the space of solutions. As a consequence of AdS/CFT conjecture we expect a duality between the solutions to these two sets of equations at least in certain regime. The goal of this talk would be to explore this
duality between these two very different systems.


 

Speaker:

Dr. Sourish Basu (SRON Netherlands Institute for Space Research, Utrecht, Netherlands)

Title:

Detecting biomass burning emission over South East Asia from space.

Date:

August 12th, 2013

Time:

04:00 pm - 05:00 pm.

Venue:

FB 382

Abstract:

Among the different components constituting anthropogenic CO2 emissions, biomass burning is the most uncertain. Current methods to quantify emissions from biomass burning -- such as forest fires and agricultural waste burning -- include satellite imaging to detect burnt areas and smoke plumes. However, these methods often underestimate large fire events since satellite are blind in the presence of smoke and aerosols that accompany large fires. I will describe a different -- and still developing -- method to quantify biomass burning emissions, which is to derive surface fluxes of CO and CO2 from observed gradients of those gases. Since most areas with widespread fires are devoid of surface monitoring stations, the observed gradients will be derived from satellite data. I will show how, using independent measurements of CO and CO2, we can detect fire events and quantify the amount of biomass burned.


 

Speaker:

Dr. Pintu Das (Institute of Physics, Goethe University – Frankfurt, Germany)

Title:

Magnetization dynamics in nano-/micro-structures using 2DEG-based micro-Hall magnetometry

Date:

August 8th, 2013

Time:

04:00 pm - 05:00 pm.

Venue:

FB 382

Abstract:

With the fast development of data storage technologies, studying the magnetization as well as domain-wall dynamics in magnetic nano- as well as micro-structures have recently found immense attention of researchers active in the field of magnetism [1]. Investigations have been carried out for arrays or assembly of magnetic particles of nanometer scale dimensions. However, measurements of assembly of particles lead to an average signal and during this process many interesting and important information get lost resulting in an incomplete understanding of the internal dynamics of individual domains or domain walls. Therefore, investigations of individual (i.e., single) magnetic entities of nano-/micron-scale dimensions are important in order to understand the magnetization process in great details. Such data can also be directly used to test the existing theories [2].
Motivated by these factors, we performed magnetic measurements of single ferromagnetic particles of micron and nano-scale dimensions using micro-Hall magnetometry method based on two-dimensional-electron-gas (2DEG) in the heterostructure of GaAs/AlGaAs. In this talk, I will discuss the results of measurements on a single CrO2 micro-crystal. With our high-sensitive measurement method, we were able to observe the transition from three-domain state to a two-domain state with a single domain-wall (separating the two domains), which was supported by micro-magnetic simulations [3]. Furthermore, we were able to track the motion of the domain wall through the sample and observed Barkhausen jumps due to the interaction with the pinning centres. Overall, the results demonstrate that micro-Hall magnetometry measurements can be used to obtain quantitative and detailed information of magnetization reversal process in individual particles of nano and micron scale dimensions. The results also allow us to estimate the density of pinning centres as a function of temperature. References:
[1] S. Parkin et al, Science, 320, 190 (2008).
[2] K. S. Novoselov et al, Nature 426, 812 (2003).
[3] P. Das et al., Appl. Phys. Lett. 97, 042507 (2010); J. App. Phys. 112, 053921 (2012).

QuiC Talk:

Speaker:

Dr. Anand K. Jha (Dept. Of Physics, IIT Kanpur)

Title:

Temporal Coherence in Two-Photon Interference - II

Date:

July 4th, 2013

Time:

11:00 am - 12:00 noon.

Venue:

FB 482


 

Speaker:

Dr. Anand K. Jha (Dept. Of Physics, IIT Kanpur)

Title:

Temporal Coherence in Two-Photon Interference

Date:

June 18th, 2013

Time:

11:00 am - 12:00 noon.

Venue:

FB 482

Abstract:

In the earlier two talks, we had discussed two-photon interference and
entanglement from a very broad perspective. The aim of this talk (and the
next few) is to get into in-depth discussions about two-photon
interference and related phenomena. In this talk we will be discussing the
role of temporal coherence and indistinguishability in two-photon
interference. We will keep our discussions of temporal coherence centered
around parametric down-conversion, a non-linear optical phenomenon that
produces entangled two-photon field.


 

Speaker:

Dr. Kedar B. Khare (Dept. Of Physics, IIT Delhi)

Title:

How many measurements are needed to generate an N-pixel image?

Date:

June 10th, 2013

Time:

11:00 am - 12:00 noon.

Venue:

FB 382

Abstract:

In Scientific and Technological research ranging from sub-nano to astronomical length scales, imaging systems are playing a key role as tools that allow us to visualize natural phenomena or objects of interest,thereby, directly influencing new discoveries. With ever increasing demands on imaging performance (e.g. resolution, speed, sensitivity to
noise, etc.), it is becoming clear that imaging systems of tomorrow need to acquire, process and utilize imaging data in an efficient non-redundant manner. In this seminar I will discuss some current ideas on imagerecovery from "incomplete" or sub-Nyquist sampled data with examples from my own research work in diagnostic healthcare and optical imaging. It will be shown that a hybrid approach - combining imaging hardware and new image recovery algorithm ideas - allows us to overcome conventionally perceived limits on imaging systems.

High Energy Physics Seminar:

Speaker:

Dr. Anurag Sahay ( Inst. of Physics, Bhubaneswar)

Title:

Tunnelling in Anti de Sitter Space and in its Boundary Matrix Dual

Date:

07.06.2013 ( Friday)

Time:

4:00 PM

Venue:

FB 382

Abstract:

For charged black hole, within the grand canonical ensemble, the decay rate from thermal AdS to the black hole at a fixed high temperature increases with the chemical potential. We check that this feature is well captured by a phenomenological matrix model expected to describe its strongly coupled dual. This comparison is made by explicitly constructing the kink and bounce solutions around the de-confinement transition and
evaluating the matrix model effective potential on the solutions.

QuIC Talk (Quantum Information and Coherence)

Speaker:

Dr. Anand Kumar Jha (Dept. Of Physics, IIT Kanpur)

Title:

Two-Phonton Interference and Entanglement - II

Date:

May 7th, 2013 (Friday)

Time:

4:15-5:15 pm

Venue:

FB-382

QuIC

Speaker:

Dr. Anand Kumar Jha (Dept. Of Physics, IIT Kanpur)

Title:

Two-Phonton Interference and Entanglement - I

Date:

May 3rd, 2013 (Friday)

Time:

3:45-5:00 pm

Venue:

FB-382

Seminar:

Speaker:

Prof. S. Dutta Gupta (University of Hyderabad, Hyderabad)

Title:

Bending light the wrong way!

Date:

17 April 2013

Time:

3.00 PM

Venue:

FB 382

HEP:

Speaker:

Ravi Manohar (IITK)

Title:

A lightfront non-perturbative study of generalized parton distributions

Date:

March 12, Tuesday

Time:

4 pm

Venue:

FB-382

Abstract:

We give a study of interface between the nonperturbative lightfront amplitude calculation for an electron in a trap and an experimentally-accessible distribution functions using such light front amplitudes. It will be helpful to investigate these distribution functions at weak (QED) coupling as well as at an artificially large coupling. Additionally it will be interesting to map out the effects of a confining potential (external harmonic oscillator) trap on these distribution functions. Epoch to this project, we investigate the generalized parton distributions H(x,\zeta;,t) in the forward limit for a dressed-electron using the nonperturbative lightfront amplitude calculated in the harmonic oscillator basis.


 

Speaker:

Mridupawan Deka (JINR, Dubna, Russia).

Title:

Quark and Gluon Angular Momenta Contributions to Nucleon Spin

Date:

26 February, Tuesday

Time:

4 pm

Venue:

FB-382

Abstract:

The nucleon spin structure has been a longstanding issue in hadronic physics, both experimentally and theoretically. From the polarized Deep Inelastic Scattering experiments and Lattice QCD calculations, it has been found that the contribution coming from the quark spin is rather small (~25%). Now, it is widely accepted that the rest of the nucleon spin should come from the gluon spin and the orbital angular momenta of quarks and gluons. In this talk, I will present a complete Lattice QCD calculation of the quark and glue angular momenta inside a proton. The calculation is carried out on a 16^3×24 quenched lattice using the standard Wilson action.

Seminar:

Speaker:

Dr. R. Chelakkot, School of Engineering and Applied Sciences (SEAS), Harvard University, USA

Title:

Semiflexible polymers: Instabilities under confinement,
constraint and activity.

Date:

18 February (Monday)

Time:

4:00 PM

Venue:

FB 382

HEP:

Speaker:

Bindusar Sahoo (Nikhef, Amsterdam)

Title:

Topologically massive higher-spin gravity

Date:

February 13, wednesday

Time:

4 pm

Venue:

FB-382

Abstract:

In the last couple of decades a theory has been developed by Vasiliev to consider interacting theories of fields with spin greater than 2 which is known as higher-spin gravity. This theory has received a lot of attention recently in the context of AdS-CFT correspondence. The theory in various dimensions is conjectured to be dual to well known conformal field theories in the boundary. In the light of this recent development, we will discuss the higher-spin analogue of topologically massive gravity in three dimensions, which we call topologically massive higher-spin gravity. We will start with a brief introduction and motivation to consider higher-spin theories. This will be followed by a brief introduction and overview of current results in higher-spin theories and topologically massive gravity. This will be followed by our work on topologically massive higher-spin gravity. We will discuss various semi classical as well as quantum results of the theory considered by us.


 

Speaker:

Arnab Kundu (Univ of Texas at Austin)

Title:

Dynamics of Fundamental Flavours in Holographic Duals of Large N Gauge Theories.

Date:

Feb 4, 2013 Monday

Time:

2:30 pm

Venue:

FB-382

Abstract:

Using the gauge-gravity duality, more specifically the AdS/CFT correspondence, we will discuss strongly coupled dynamics of fundamental flavours in large N gauge theories. We will primarily focus on the physics of chiral symmetry breaking by introducing flavour degrees of freedom in the so called Klebanov-Witten model. We will discuss the physics of the flavour sector in and beyond the probe limit. We will conclude with some general remarks.

Seminar:

Speaker:

Dr. Umakanta Tripathy (Visiting Scientist, TIFR, Mumbai)

Title:

Detecting malaria and imaging extra cellular matrix in tissues by multi-modal nonlinear laser scanning microscopy (NLSM)

Date:

5th February, 2013

Time:

12:00 noon

Venue:

FB 382

Abstract:

Multi-modal nonlinear laser scanning microscopy (NLSM), also known as multiphoton microscopy or higher harmonic generation microscopy is a powerful research tool that combines the advanced optical techniques of laser scanning microscopy with long wavelength multi- photon fluorescence excitation to capture high resolution and threedimensional (3D) images of specimens. Some of the core advantages that include label free imaging, depth imaging & minimizing photo-bleaching allows investigations on thick, living and fixed cells/tissues that would not otherwise be possible with conventional imaging techniques. Two-photon fluorescence (TPF), second harmonic generation (SHG), & third harmonic generation (THG) techniques are used as imaging tools. In the present talk, we will focus the use of multi-modal NLSM as an imaging device for the early detection and quantification of the malaria pigment (hemozoin) by THG technique. The obtained results will guide the optimal design of malaria detection technologies that exploit the THG response of hemozoin. In addition, multi-modal NLSM imaging of extra cellular matrix in tissues (collagen and elastin) to investigate the structural remodeling of the human ascending aorta with dilation, and documenting the geometrical properties of vocal folds (human & porcine) by SHG and TPF technique will also be presented. The results acquired would provide valuable information for better understanding the tissue biomechanics that may assist clinicians for rapid and reliable disease diagnosis.

HEP:

Speaker:

Prof. Dharam Vir Ahluwalia (Universidade Estadual de Campinas, Brazil
and TIFR)

Title:

Elko Spinors and dark matter

Date:

17 January, Thursday

Time:

11 AM - 1 PM and 4 PM - 6 PM (with refreshment breaks)

Venue:

382 FB

Seminar:

Speaker:

Dr. Prasanna Kulkarni,
( Departamento de Fisica de la MateriaCondensada,Universidad Autonoma de Madrid, Madrid,Spain )

Title:

Elko Spinors and dark matter

Date:

17 January, Thursday

Time:

11 AM - 1 PM and 4 PM - 6 PM (with refreshment breaks)

Venue:

382 FB 


 

Speaker:
Title:
Date:
Time:
Venue:

Purnendu Chakraborty
Gluon condensate and nonperturbative QCD propagators above deconfinement temperature
02 Jan 2013 (Wednesday)
4:00 PM (FB382)


 

Speaker:
Title:
Date:
Time:
Venue:

Udai Raj Singh
Inhomogeneous superconducting gap and symmetry breaking in FeSe0.4Te0.6 studied by spectroscopic imaging STM
27 Dec 2012 (Thursday)
11:00 AM (FB382)


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. T. Arun Kumar
Study of perfluoropolymer as an alignment layer for nematic liquid crystals
27 Dec 2012 (Thursday)
4:00 PM
FB382


 

Speaker:
Title:
Date:
Time:
Venue:

Prof. Dharam Vir Ahluwalia
Elko Dark Matter
24 Dec 2012 (Monday)
4:00 PM
FB382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Amar Nath Gupta
Transition path time, diffusion constant and folding rate of protein determined from reconstructed free-energy landscape analysis
12 Dec 2012 (Wednesday)
4:00 PM (FB382)


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Shiva Kumar Malapaka, Leeds University, UK
A study of magnetic helicity in forced and decaying 3D-MHD turbulence
4 pm
FB-382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Anindya Das
Superconductor-semiconductor junctions: Cooper pairs splitting and Majorana quasiparticles
22 Nov 2012 (Thursday)
4:00 PM (FB382)


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Naveen Kumar
Relativistic beam-plasma interaction and its applications for particle acceleration and fast ignition fusion in plasmaa
20 Nov 2012 (Tuesday)
11:00 am
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

T. K. Saxena
Automation in research and industry
6th Nov 2012 (Tuesday)
4:00 pm
FB 382

Speaker:
Title:
Date:
Time:
Venue:

Dr. Dinesh Kabra, Cavendish Laboratory, University of Cambridge, UK.
Molecular Semiconductors: Charge Transport, Structural and Spectroscopic based Investigations
12 Jan 2012 (Thursday)
4:00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Swarn Lata Singh (BHU))
Free-energy functional for symmetry broken first order phase transitions
11 January 2012
4:00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Amit Agarwal (Scoula Normale, Pisa, Italy)
Collective excitations in strongly spin-orbit coupled two dimensional electron gases
2 January 2012
4:00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Pomita Ghoshal (HRI)
Determining the Neutrino Mass Hierarchy via Future Atmospheric Neutrino Detectors
December 30 (Friday)
4:00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Chary Rangayajulu, University of Saskatchewan, Canada
Laser Compton Scatter MeV Photons at Light Sources for Nuclear andAllied Sciences
19th December, 2011 (Monday)
4:00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Amit Sharma, Seagate Technology, USA
An Integrated Heat Assisted Magnetic Recording System
2nd November, 2011 (Wednesday)
2.30 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Gopal, IITK
Collider Implication of Weyl Meson.
18 October, Tuesday
4.00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

M. Ranaul Islam (Strathclyde University, Glasgow, UK)
Laser Wakefield Accelerator: Towards Gamma-Rays
17 October, 2011
4.00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Anand Kumar Jha, Intel Corporation, USA
Two-Photon Fields: Coherence, Interference and Entanglement
27 September, 2011 (Tuesday)
4.00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Kaushik Bhattacharya (IITK)
Lee-Wick thermodynamics and its effect in the early universe
20 Sept, 2011, Tuesday
4.00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Soumen Mandal, Institut Neel, CNRS and Universite Joseph Fourier,BP 166, 38042 Grenoble cedex 09, France
Diamond as a material for nano-mechanical and quantum devices
7 Sept, Wednesday
4.00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Archana Tiwari, School of Chemical and Physical Sciences, Sikkim University
Fluorescent balls with an effective spin
06 Sept 2011 (Tuesday)
2.30 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Prabhakar Tiwari (IITK)
Large Scale Alignments in Quasar Polarizations due to pseudoscalar-photon mixing in intergalactic magnetic fields
Sept 06, Tuesday
4.00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Swati Bhattacharya (Univ. of Illinois, Urbana, USA)
Designing nanopore sensors: laying the foundations of personalgenomics
5 September, 2011
4.00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dipankar Chakrabarti (IIT Kanpur)
A study of generalized parton distributions in position space.
23 Aug, Tuesday
4.00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Udit Raha (Univ. Basel)
Electromagnetic Pion and Kaon Form Factors in Light-cone QCD
17 Aug, Wednessday
5.00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Kumar Rao (Helsinki Univ)
Top Polarization as a probe of New Physics
02 Aug(Tuesday), 2011
4.00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Amitesh Paul, Technische Universität München, Germany
Polarized neutron scattering in nano-layered systems
01 August 2011 (Monday)
4.00 pm to 5.00 pm
FB 382

Speaker:
Title:
Date:
Time:
Venue:

Prof. Deepak Kumar (JNU)
Anomalous heat transport in quantum chains
27 July 2011
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dinesh Kumar Shukla, Deutsches Elektronen-Synchrotron (DESY), Hamburg, Germany
Resonant and non-resonant magnetic x-ray scattering on multiferroic HoFe3(BO3)4
29 July 2011 (Friday)
3.00 pm to 4.00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Subhadeep De, Joint Quantum Institute (JQI), National Institute for Standards and Technology (NIST) and University of Maryland (UMD), Maryland, USA.
Facility to produce ultra-cold degenerate Bose and Fermi gasses
21 July 2011 (Thursday)
4:00pm FB-382.


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Bhaskaran Muralidharan, MIT,USA
Microscopic modeling of non equilibrium electronic and thermoelectric transport phenomena at nanoscale
15 March, 2011 (Tesday)
3:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Proffesor B.S. Acharya, TIFR, Mumbai
The universe viewed in Gamma rays
4 March, 2011 (Friday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Proffesor Anjan Kumar Gupta, IIT Kanpur
STM trip induced carrier doping in graphene with puddles
4 March, 2011 (Friday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Vinod Chandra Joshi, TIFR, Mumbai
A quasi particle description for (2+1)-flavor equation of state
15 February, 2011 (Tuesday)
4.00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Proffesor Sukanta Panda, IISER, Bhopal
Detecting high to ultra high energy cosmic ray
11 February, 2011 (Friday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Narendra Sahu, Uni. Libre de Bruxelles, Belgium
Direct and indirect search of dark matter interacting via Higgs Portal
8 February, 2011 (Tuesday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Professor sanjoy Swain, NEISER, Bhubaneswar
Introducing to Large Hadron Collider (LHC)
28 January, 2011 (Friday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. T.R. Govindarajan, Institue of Mathematical Science
Gravity and Geometry-Hundreds year after Einstein
17 January, 2011 (Monday)
11:30 AM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Jayanti Prasad, IUCAA, Pune
Cosmological N-body simulatio: Techniques, scope limitation
18 January, 2011 (Tuesday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Professor Steven Tomsovic, Washington State University
What is measured in the scanning gate microscopy of a quantum point contact?
13 January, 2011 (Thursday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Bhaskaran Muralidharan, MIT,USA
Microscopic modeling of non equilibrium electronic and thermoelectric transport phenomena at nanoscale
15 March, 2011 (Tesday)
3:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Proffesor B.S. Acharya, TIFR, Mumbai
The universe viewed in Gamma rays
4 March, 2011 (Friday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Proffesor Anjan Kumar Gupta, IIT Kanpur
STM trip induced carrier doping in graphene with puddles
4 March, 2011 (Friday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Vinod Chandra Joshi, TIFR, Mumbai
A quasi particle description for (2+1)-flavor equation of state
15 February, 2011 (Tuesday)
4.00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Proffesor Sukanta Panda, IISER, Bhopal
Detecting high to ultra high energy cosmic ray
11 February, 2011 (Friday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Narendra Sahu, Uni. Libre de Bruxelles, Belgium
Direct and indirect search of dark matter interacting via Higgs Portal
8 February, 2011 (Tuesday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Professor sanjoy Swain, NEISER, Bhubaneswar
Introducing to Large Hadron Collider (LHC)
28 January, 2011 (Friday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. T.R. Govindarajan, Institue of Mathematical Science
Gravity and Geometry-Hundreds year after Einstein
17 January, 2011 (Monday)
11:30 AM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Jayanti Prasad, IUCAA, Pune
Cosmological N-body simulatio: Techniques, scope limitation
18 January, 2011 (Tuesday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Professor Steven Tomsovic, Washington State University
What is measured in the scanning gate microscopy of a quantum point contact?
13 January, 2011 (Thursday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. A. Nagar (Max-Planck Institute, Golm, Germany)
Effect of mutators on evolution
11 November 2010 (cancelled)
4.00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Deepshikha Jaiswal-Nagar Goethe University, Frankfurt
Magnetocaloric effect and magnetic cooling near a field-induced Quantum-critical point
12 November 2010 (Friday)(cancelled)
4.00 pm to 5.00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. N.S. Vidhyadhiraja (JNCASR, Bangalore)
Dynamics and transport in paramagnetic heavy fermion systems.
10 November 2010 (Wednesday)
4.00 pm to 5.00 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Rajib Sarkar, Max-Planck Institute CPfS, Dresden, Germany
Interplay between Ce-4f and Fe-3d magnetism in CeFe(As/P)O as seen by NMR.
1st November (Monday)
Time: 3:0 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Debaprasad Maity , National Taiwan University
Some issues on Randall-Sundrum Brane World models
26 October, 2010, Tuesday
5 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Sarmistha Banik
Effect of Shear Viscosity on the Nucleation of Antikaon Condensed Matter in Neutron Stars
20 October, Wednesday
4:00pm
FB-382.


 

Speaker:
Title:
Date:
Time:
Venue:

Anand Sengupta(Delhi Univ)
Search for gravitational waves from binary blackholes in LIGO's S5 data
29th sept, Wednessday
4 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Pankaj Jain, IIT Kanpur
Local Scale Invariance may solve the cosmological constant problem
September 14, Tuesday
4 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. M. K. Niranjan (IIT, Hyderabad)
Novel Interface Magnetoelectric Effects in Oxide Heterostructures: Design and prediction from first-principles
23 Aug4 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Pankaj Jain
Local Scale Invariance may solve the cosmological constant problem
September 7, Tuesday (postponed)
4 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Naveen Surendran, ICTP, Trieste, Italy
Topological order in three dimensions
14 May 2010
4 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. P. Ghosh (ICTP, Trieste)
Atomistic modeling of materials
13 May 2010
4 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. K. S. Nagapriya, Israel
Torsional Electromechanics of Carbon and Inorganic Nanotubes
Tue, 20 April 2010
5.15 pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Abhijit Samanta (HRI)
Atmospheric neutrinos in future neutrino oscillation experiments
20 th April (Tuesday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Naveen Kumar Singh
Effective Field theory of Gravity
March 23, 2010 (Tuesday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Prof. J Maharana
Axion Dilaton Q Cosmology.
March 18 ,2010 (Thursday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Arnab Chatterjee, The Abdus Salam International Centre for Theoretical Physics, Trieste, Italy
Effective Field theory of Gravity
15th March,2010 4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Prof. P. Majumdar (SINP)
Effective Field theory of Gravity
March 11 (Thursday)
4:30 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Naveen Kumar Singh (Postponed)
Effective Field theory of Gravity
March 09, 2010 (Tuesday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. P S Mohanty, University of Fribourg, Switzerland
Responsive Colloids as a Model System in Condensed Matter Physics
22 February, Monday
4-5 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Kaushik Bhattacharya
An unusual extension of statistical mechanics in the unusual quantum field theory.
23 February, Tuesday
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Prof. Avinash Khare, IOP, Bhubaneshwar
Supersymmetric Quantum Mechanics
17 February, Wednesday and 18 February, Thursday
4-6 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Suresh Govindarajan (IIT Chennai)
New Lie algebras from dyonic black holes
21 January 2010 (Thursday)
4:00pm
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. A.K. Shukla, Institut Jean Lamour, UMR 7198 CNRS, 54042 Nancy, France
Metal adlayers grown on quasicrystalline surfaces
15th January 2010 (Friday)
12:00 Noon
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Akhlesh Lakhtakia
Copycat science and technology
04 Jan 2010 (Monday)
4:00 p.m. to 5:00 p.m.
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Vinod Chandra Joshi (TIFR)
Properties of hot and dense matter produced in heavy ion collisions
January 5, 2010
4:00pm (tea @ 3:45pm)
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Prof. Govind Swarup, NCRA, TIFR, Pune
New Questions at the Frontiers of Radio Astronomy: Giant Metrewave Radio Telescope near Pune, Recent Results and Challenging Projects
10 December, 2009, Thursday 4 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Aakash Basu, Department of Applied Physics, Stanford University
Mechanochemistry of DNA Gyrase - a processive molecular motor
24 November (Tuesday)
2.30 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Rajeev Bhalerao (TIFR, Mumbai)
Transport properties of the fluid produced at RHIC
24 November, Tuesday
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Golam M Hossain (University of New Brunswick, Canada)
Driving cosmic inflation on a bumpy road
November 3, Tuesday
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. Aveek Bid, Weizmann Institute of Science, Israel
Euclidean formulation in black hole thermodynamics
October 28, 2009 (Wednesday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Anurag Sahay
Euclidean formulation in black hole thermodynamics
27/10/09, Tuesday (postponed)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

A. Pavan Kumar
CMB polarization power spectrum and its Estimation
October 20, Tuesday
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Prof. R Ramachandran (IISER, Pune)
Are there massive long lived states in string theory?
October 16, Friday
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr. G.N. Shanmugha Sundaram
SKA Design, Evalution, Optimization Issuses
September 16 (Wednesday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Pankaj Jain
Conformal Standard Model
September 2 (Wednesday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr T Sarkar
Recent Developements on helium core white dwarf stars
25 August (Tuesday)
4:00 PM
FB 382


 

Speaker:
Title:
Date:
Time:
Venue:

Dr Arunansu Sil
Inflation and Supersymmetry Breaking
18 August (Tuesday)
4:00 PM
FB 382


 

Speaker:
Institution:
Title:

Date:

Arindam Kundagrami
University of Massachusetts, Amherst, USA
Physics of charged polymers: effective charge, size, phase
transitions, and other properties as soft materials
March 2, 2009


 

Speaker:
Institution:
Title:

Date:

Archana Pai
Max Planck Institute fur Gravitationsphysik
Fishing gravitational wave chirps with a
multi-detector network
December 29, 2008

Horizon Lecture

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Deepak Mathur
UM-DAE CBS and TIFR, Mumbai
Adventures on the interface of physics and biology
November 8, 2008

Fourth Prof. Jagadishwar Mahanty Lecture

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Title:

Date:

Deepak Mathur
UM-DAE CBS and TIFR, Mumbai
Interaction of intense light with matter....
and of matter with intense light
November 7, 2008


 

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Date:

Arul Lakshminarayan
IIT Madras
Some Instances of Extreme Value Statistics
in Physics
October 23, 2008


 

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Date:

Dipankar Chakraborti.
University of Wales Swansea, UK
Diffraction pattern in deeply virtual
Compton scattering
August 8, 2008


 

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Institution:
Title:

Date:

Nilotpal Ghosh
University of Leipzig, Germany
Andreev Reflection and Physical Property
Measurements
August 4, 2008

Speaker
Affiliation
Title
Date

Hemant Shukla
University of California, Berkeley
Simulating the Supernova/Acceleration Probe (SNAP) Mission for Exploring Dark Energy
March 28, 2008


 

Speaker
Affiliation
Title

Date

Ajit M. Srivastava
Institute of Physics, Bhubenswar
Super-horizon fluctuations and acoustic oscillations in relativistic heavy-ion collisions
March 13, 2008


 

Speaker
Affiliation
Title
Date

Douglas W. McKay
IIT Kanpur and Univ. of Kansas.
Examining the Cosmic Ray Knee
February 14, 2008


 

Speaker
Affiliation
Title
Date

P.K. Panigrahi
Physical Research Laboratory, Ahmedabad
Solitons in Bose Einstein Condensates (BEC) in a Trap and Optical Lattice
September 5, 2007


 

Speaker
Affiliation
Title

Date

Colin Benjamin
Centre de Physique, Marseille, France
Controllable pi junction in a Josephson quantum-dot device with molecular spin
August 10, 2007


 

Speaker
Affiliation
Title
Date

Udit Raha
University of Basel, USA
Hadronic Atoms In Effective Field Theory
August 3, 2007


 

Speaker
Affiliation
Title

Date

Vishal Saxena
University of Southern California, USA
A Non-invasive Multimodal Technique to Monitor Brain Tumour Vascularization
April 26, 2007


 

Speaker
Affiliation
Title
Date

Vishal Saxena
University of Southern California, USA
Hot Electron Luminiscence in GaAs : Electric Field Effects
April 25, 2007


 

Speaker
Affiliation
Title
Date

Ambar Jain
MIT, USA
Penguin Loops for Nonleptonic B decays in the Standard Model
April 23, 2007


 

Speaker
Affiliation
Title

Date

Pankaj Jain
IIT, Kanpur, India
Cosmological Symmetry Breaking, Pseudo-scale invariance, Dark Energy and the Standard Model
April 11, 2007


 

Speaker
Affiliation
Title
Date

Indrajit Mitra
IIT, Kanpur, India
Criterion for dynamical chiral symmetry breaking
April 03, 2007


 

Speaker
Affiliation
Title
Date

Shiraz Minwalla
TIFR, Mumbai, India
Black holes in Yang-Mills Theories
March 29, 2007


 

Speaker
Affiliation
Title
Date

Amihay Hanany
MIT, USA
Tiling dimers and quiver gauge theories
March 22, 2007


 

Speaker
Affiliation
Title
Date

A. Taraphder
IIT, Kharagpur
Magnetic and orbital order in doped magnetoresistive systems
March 20, 2007


 

Speaker
Affiliation
Title

Date

Narendra Sahu
PRL, Ahmedabad
A predictable unified model for dark matter, dark energy, neutrino masses and leptogenesis at the TeV scale
March 12, 2007


 

Speaker
Affiliation
Title
Date

R. Rajesh
IMSc, Chennai
Statistics of Driven Dissipative Systems
March 01, 2007


 

Speaker
Affiliation
Title
Date

R. Ramachandran
IISER, Pune
Decay of Massive String States
February 28, 2007


 

Speaker
Affiliation
Title
Date

Balaji Birajdar
Institute of Applied Physics, University of Tuebingen, Tuebinge, Germany
Transmission Electron Microscopy of Superconducting MgB2 Tapes
February 08, 2007


 

Speaker
Affiliation
Title
Date

Justin Raj David
HRI,Allahabad
From Spacetime to Worldsheet: Four Point Correlators
February 01, 2007


 

Speaker
Affiliation
Title
Date

Amit Ghoshal
UCLA,USA
Diamagnetism of Nodal Fermions: Graphene and Others
January 18, 2007


 

Speaker
Affiliation
Title
Date

Prasant Panigrahi
PRL, Ahmedabad
Study of Fluctuations through Wavelet Transform
December 29, 2006


 

Speaker
Affiliation
Title
Date

T.K. Ghosh
JEPS, Okayama, Japan

December 27, 2006


 

Speaker
Affiliation
Title
Date

Umananda Dev Goswami
Guwahati University
Charmed Hadron Production in pp Interaction
December 6, 2006


 

Speaker
Affiliation
Title
Date

Gopika Sood
Punjab University
Fluctuations with WA98 and STAR
November 24, 2006


 

Speaker
Affiliation
Title
Date

Bhag Chauhan
CFTP-Instituto Superior Technico, Lisbon
Solar Neutrinos: Oscillations and Magnetic Moment
November 17, 2006


 

Speaker
Affiliation
Title
Date

Prakash Mathews
SINP, Kolkata
QCD Prerequisites for Extra Dimensional Searches
November 16, 2006


 

Speaker
Affiliation
Title
Date

Rajarshi Ray
SINP, Kolkata
QCD Thermodynamics: Lattice and PNJL Model
November 13, 2006


 

Speaker
Affiliation
Title
Date

Dimitry Batani
Universita di Milano Bicocca, Italy
Transport of Intense Laser-produced Electron Beams in Matter
October 30, 2006


 

Speaker
Affiliation
Title
Date

Swarnendu Sarkar
IOP, Bhubaneshwar
Phases of Asymptotically AdS Black Holes and Gauge Theory
October 26, 2006


 

Speaker
Affiliation
Title
Date

A.K. Grover
TIFR, Mumbai

October 12, 2006


 

Speaker
Affiliation
Title
Date

K. Narayanan
TIFR,Mumbai India
Time Dependent Phenomena in String Theory
October 9, 2006


 

Speaker
Affiliation
Title
Date

Sumathi Rao
HRI, Allahabad
Correlated Electron Transport Through Junctions of Quantum Wires
September 19, 2006


 

Speaker
Affiliation
Title
Date

Manoj Gopalakrishnan
HRI, Allahabad
Stochastic Theory of Ligand Binding to Cell Membrane Surfaces
August 18, 2006


 

Speaker
Affiliation
Title
Date

Subrata Bal
Dublin Institute for Advanced Studies
Dynamical Generation of Gauge Group in Matrix Model
April 18, 2006


 

Speaker
Affiliation
Title
Date

E. Harikumar
University of Sau Paulo, Brazil
Dirac Operator on the q-deformed Fuzzy Sphere and its Spectrum
April 17, 2006


 

Speaker
Affiliation
Title
Date

S. Ramakrishnan
TIFR, Mumbai
Multiple Phase Transitions in� RE5T4M10 (T=Rh, Ir and� M=Si, Ge, Sn) Compunds
April 14, 2006


 

Speaker
Affiliation
Title
Date

Dieter Suter
University of Dortmund
Quantum Computing: Towards Scalability
March 13, 2006


 

Speaker
Affiliation
Title
Date

Arun Bansil
Northeastern University, Boston
Modelling Electronic Structure and Spectroscopy of Complex Materials: ARPES, RIXS and STM
March 06, 2006


 

Speaker
Affiliation
Title
Date

Shailendra Kumar
Center for Advanced Technology, Indore
Role of Plasma Waves and Thermal Waves in Study of Semiconductors
March 01, 2006


 

Speaker
Affiliation
Title
Date

Tapobrata Sarkar
Indian Institute of Technology, Kanpur
Closed String Tachyons: Recent Developments
February 23, 2006


 

Speaker
Affiliation
Title
Date

Som Bandyopadhyay
University of Calgary
Monogamy of Quantum Entanglement
February 20, 2006


 

Speaker
Affiliation
Title
Date

Pankaj Jain
Indian Institute of Technology, Kanpur
Interferometric Parallax: A Method for Measurement of Astronomical Distances
January 20, 2006


 

Speaker
Affiliation
Title
Date

Brian Dolan
National University of Ireland, Maynooth
Quantum Black holes: The Event Horizon as a Fuzzy Sphere
January 13, 2006


 

Speaker
Affiliation
Title
Date

Chiranjib Mitra
University College of London
Electron Doped Manganites and their Spin Density of States from Tunneling Magnetoresistance and Spectroscopic Studies
January 03, 2006


 

Speaker
Affiliation
Title
Date

Rajendra Singh
Max-Planck Institute of Microstructure Physics, Weinberg (Germany)
Strained Silicon On Insulator via Wafer Bonding and Layer Transfer Approach for Nano CMOS Applications
November 22, 2005


 

Speaker
Affiliation
Title
Date

Chandan Dasgupta
Indian Institute of Science, Bangalore
Density Functional Theory of Hard Sphere Glasses
November 18, 2005


 

Speaker
Affiliation
Title
Date

Arijit Bhattacharya
University of Padova, Italy
Dynamics of Pattern Formation in Reaction Diffusion Systems
November 17, 2005


 

Speaker
Affiliation
Title
Date

Ninad Shinde
Nagoya University, Japan
Solid-State Physics Using Ion Beams: Spectroscopy and Irradiation Effects
November 8, 2005


 

Speaker
Affiliation
Title
Date

Jyotipratim Ray Choudhury
University of Burhawan, West Bengal
A Semiclassical Approach to Kramer�s Problem
October 31, 2005


 

Speaker
Affiliation
Title
Date

Dipankar Chakrabarti
University of Florida
Helicity Non-Conserving Glu-Glue Scattering Amplitudes on the Light-Cone Worldsheet
October 25, 2005


 

Speaker
Affiliation
Title
Date

Rajesh Narayanan
University of Karlsruhe, Germany
Griffiths Phase in Unconventional Quantum Hall Effect
October 25, 2005